Use different syntax for checks that matter to typestate

This giant commit changes the syntax of Rust to use "assert" for
"check" expressions that didn't mean anything to the typestate
system, and continue using "check" for checks that are used as
part of typestate checking.

Most of the changes are just replacing "check" with "assert" in test
cases and rustc.

src/boot/fe/item.ml

@@ -199,6 +199,14 @@ and parse_stmts_including_none (ps:pstate) : Ast.stmt array =
           bump ps;
           expect ps SEMI;
           [| span ps apos (lexpos ps) Ast.STMT_cont |]
+      | ASSERT ->
+          bump ps;
+          let (stmts, expr) =
+             ctxt "stmts: check value" parse_expr ps
+          in
+              expect ps SEMI;
+              spans ps stmts apos (Ast.STMT_check_expr expr)
+(* leaving check as it is; adding assert as a synonym for the "old" check *)
       | CHECK ->
           bump ps;
           begin

src/boot/fe/lexer.mll

@@ -92,6 +92,7 @@
 
                 ("type", TYPE);
                 ("check", CHECK);
+                ("assert", ASSERT); 
                 ("claim", CLAIM);
                 ("prove", PROVE);
 

src/boot/fe/token.ml

@@ -77,6 +77,7 @@ type token =
   (* Type and type-state keywords *)
   | TYPE
   | CHECK
+  | ASSERT
   | CLAIM
   | PROVE
 
@@ -237,6 +238,7 @@ let rec string_of_tok t =
     (* Type and type-state keywords *)
     | TYPE       -> "type"
     | CHECK      -> "check"
+    | ASSERT     -> "assert"
     | CLAIM      -> "claim"
     | PROVE      -> "prove"
 

src/comp/front/ast.rs

@@ -283,7 +283,10 @@ tag expr_ {
     expr_put(option.t[@expr], ann);
     expr_be(@expr, ann);
     expr_log(int, @expr, ann);
-    expr_check_expr(@expr, ann);
+/* just an assert, no significance to typestate */
+    expr_assert(@expr, ann);
+/* preds that typestate is aware of */
+    expr_check(@expr, ann);
     expr_port(ann);
     expr_chan(@expr, ann);
 }

src/comp/front/creader.rs

@@ -93,7 +93,7 @@ fn parse_ty(@pstate st, str_def sd) -> ty.t {
         case ('c') { ret ty.mk_char(st.tcx); }
         case ('s') { ret ty.mk_str(st.tcx); }
         case ('t') {
-            check(next(st) as char == '[');
+            assert (next(st) as char == '[');
             auto def = parse_def(st, sd);
             let vec[ty.t] params = vec();
             while (peek(st) as char != ']') {
@@ -108,7 +108,7 @@ fn parse_ty(@pstate st, str_def sd) -> ty.t {
         case ('P') { ret ty.mk_port(st.tcx, parse_ty(st, sd)); }
         case ('C') { ret ty.mk_chan(st.tcx, parse_ty(st, sd)); }
         case ('T') {
-            check(next(st) as char == '[');
+            assert (next(st) as char == '[');
             let vec[ty.mt] params = vec();
             while (peek(st) as char != ']') {
                 params += vec(parse_mt(st, sd));
@@ -117,7 +117,7 @@ fn parse_ty(@pstate st, str_def sd) -> ty.t {
             ret ty.mk_tup(st.tcx, params);
         }
         case ('R') {
-            check(next(st) as char == '[');
+            assert (next(st) as char == '[');
             let vec[ty.field] fields = vec();
             while (peek(st) as char != ']') {
                 auto name = "";
@@ -149,7 +149,7 @@ fn parse_ty(@pstate st, str_def sd) -> ty.t {
             ret ty.mk_native_fn(st.tcx,abi,func._0,func._1);
         }
         case ('O') {
-            check(next(st) as char == '[');
+            assert (next(st) as char == '[');
             let vec[ty.method] methods = vec();
             while (peek(st) as char != ']') {
                 auto proto;
@@ -175,9 +175,9 @@ fn parse_ty(@pstate st, str_def sd) -> ty.t {
         case ('Y') { ret ty.mk_type(st.tcx); }
         case ('#') {
             auto pos = parse_hex(st);
-            check (next(st) as char == ':');
+            assert (next(st) as char == ':');
             auto len = parse_hex(st);
-            check (next(st) as char == '#');
+            assert (next(st) as char == '#');
             alt (st.tcx.rcache.find(tup(st.crate,pos,len))) {
                 case (some[ty.t](?tt)) { ret tt; }
                 case (none[ty.t]) {
@@ -245,7 +245,7 @@ fn parse_hex(@pstate st) -> uint {
 }
 
 fn parse_ty_fn(@pstate st, str_def sd) -> tup(vec[ty.arg], ty.t) {
-    check(next(st) as char == '[');
+    assert (next(st) as char == '[');
     let vec[ty.arg] inputs = vec();
     while (peek(st) as char != ']') {
         auto mode = ast.val;

src/comp/front/lexer.rs

@@ -127,6 +127,7 @@ fn keyword_table() -> std.map.hashmap[str, token.token] {
 
     keywords.insert("type", token.TYPE);
     keywords.insert("check", token.CHECK);
+    keywords.insert("assert", token.ASSERT);
     keywords.insert("claim", token.CLAIM);
     keywords.insert("prove", token.PROVE);
 
@@ -528,7 +529,7 @@ fn scan_numeric_escape(reader rdr) -> char {
 
     auto n_hex_digits = 0;
 
-    check (rdr.curr() == '\\');
+    assert (rdr.curr() == '\\');
 
     alt (rdr.next()) {
         case ('x') { n_hex_digits = 2; }

src/comp/front/parser.rs

@@ -621,7 +621,7 @@ fn parse_path(parser p, greed g) -> ast.path {
                 if (p.peek() == token.DOT) {
                     if (g == GREEDY) {
                         p.bump();
-                        check (is_ident(p.peek()));
+                        assert (is_ident(p.peek()));
                     } else {
                         more = false;
                     }
@@ -816,19 +816,22 @@ fn parse_bottom_expr(parser p) -> @ast.expr {
             ex = ast.expr_log(0, e, ast.ann_none);
         }
 
+        case (token.ASSERT) {
+            p.bump();
+            auto e = parse_expr(p);
+            auto hi = e.span.hi;
+            ex = ast.expr_assert(e, ast.ann_none);
+        }
+
         case (token.CHECK) {
             p.bump();
-            alt (p.peek()) {
-                case (token.LPAREN) {
-                    auto e = parse_expr(p);
-                    auto hi = e.span.hi;
-                    ex = ast.expr_check_expr(e, ast.ann_none);
-                }
-                case (_) {
-                    p.get_session().unimpl("constraint-check stmt");
-                }
-            }
-        }
+            /* Should be a predicate (pure boolean function) applied to 
+             arguments that are all either slot variables or literals.
+            but the typechecker enforces that. */
+            auto e = parse_expr(p);
+            auto hi = e.span.hi;
+            ex = ast.expr_check(e, ast.ann_none);
+        } 
 
         case (token.RET) {
             p.bump();
@@ -937,7 +940,7 @@ fn expand_syntax_ext(parser p, ast.span sp,
                      &ast.path path, vec[@ast.expr] args,
                      option.t[str] body) -> ast.expr_ {
 
-    check (_vec.len[ast.ident](path.node.idents) > 0u);
+    assert (_vec.len[ast.ident](path.node.idents) > 0u);
     auto extname = path.node.idents.(0);
     if (_str.eq(extname, "fmt")) {
         auto expanded = extfmt.expand_syntax_ext(args, body);
@@ -1673,7 +1676,8 @@ fn stmt_ends_with_semi(@ast.stmt stmt) -> bool {
                 case (ast.expr_put(_,_))        { ret true; }
                 case (ast.expr_be(_,_))         { ret true; }
                 case (ast.expr_log(_,_,_))        { ret true; }
-                case (ast.expr_check_expr(_,_)) { ret true; }
+                case (ast.expr_check(_,_)) { ret true; }
+                case (ast.expr_assert(_,_)) { ret true; }
             }
         }
         // We should not be calling this on a cdir.
@@ -2157,24 +2161,24 @@ fn parse_item(parser p) -> @ast.item {
 
     alt (p.peek()) {
         case (token.CONST) {
-            check (lyr == ast.layer_value);
+            assert (lyr == ast.layer_value);
             ret parse_item_const(p);
         }
 
         case (token.FN) {
-            check (lyr == ast.layer_value);
+            assert (lyr == ast.layer_value);
             ret parse_item_fn_or_iter(p);
         }
         case (token.ITER) {
-            check (lyr == ast.layer_value);
+            assert (lyr == ast.layer_value);
             ret parse_item_fn_or_iter(p);
         }
         case (token.MOD) {
-            check (lyr == ast.layer_value);
+            assert (lyr == ast.layer_value);
             ret parse_item_mod(p);
         }
         case (token.NATIVE) {
-            check (lyr == ast.layer_value);
+            assert (lyr == ast.layer_value);
             ret parse_item_native_mod(p);
         }
         case (token.TYPE) {

src/comp/front/token.rs

@@ -89,6 +89,7 @@ tag token {
 
     /* Type and type-state keywords */
     TYPE;
+    ASSERT;
     CHECK;
     CLAIM;
     PROVE;
@@ -258,6 +259,7 @@ fn to_str(token t) -> str {
 
         /* Type and type-state keywords */
         case (TYPE) { ret "type"; }
+        case (ASSERT) { ret "assert"; }
         case (CHECK) { ret "check"; }
         case (CLAIM) { ret "claim"; }
         case (PROVE) { ret "prove"; }

src/comp/lib/llvm.rs

@@ -861,19 +861,19 @@ obj builder(BuilderRef B, @mutable bool terminated) {
 
     /* Terminators */
     fn RetVoid()  -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildRetVoid(B);
     }
 
     fn Ret(ValueRef V) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildRet(B, V);
     }
 
     fn AggregateRet(vec[ValueRef] RetVals) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildAggregateRet(B,
                                        _vec.buf[ValueRef](RetVals),
@@ -881,26 +881,26 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     }
 
     fn Br(BasicBlockRef Dest) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildBr(B, Dest);
     }
 
     fn CondBr(ValueRef If, BasicBlockRef Then,
               BasicBlockRef Else) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildCondBr(B, If, Then, Else);
     }
 
     fn Switch(ValueRef V, BasicBlockRef Else, uint NumCases) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildSwitch(B, V, Else, NumCases);
     }
 
     fn IndirectBr(ValueRef Addr, uint NumDests) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildIndirectBr(B, Addr, NumDests);
     }
@@ -909,7 +909,7 @@ obj builder(BuilderRef B, @mutable bool terminated) {
               vec[ValueRef] Args,
               BasicBlockRef Then,
               BasicBlockRef Catch) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildInvoke(B, Fn,
                                  _vec.buf[ValueRef](Args),
@@ -919,209 +919,209 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     }
 
     fn Unwind() -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildUnwind(B);
     }
 
     fn Unreachable() -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         *terminated = true;
         ret llvm.LLVMBuildUnreachable(B);
     }
 
     /* Arithmetic */
     fn Add(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildAdd(B, LHS, RHS, _str.buf(""));
     }
 
     fn NSWAdd(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNSWAdd(B, LHS, RHS, _str.buf(""));
     }
 
     fn NUWAdd(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNUWAdd(B, LHS, RHS, _str.buf(""));
     }
 
     fn FAdd(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFAdd(B, LHS, RHS, _str.buf(""));
     }
 
     fn Sub(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildSub(B, LHS, RHS, _str.buf(""));
     }
 
     fn NSWSub(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNSWSub(B, LHS, RHS, _str.buf(""));
     }
 
     fn NUWSub(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNUWSub(B, LHS, RHS, _str.buf(""));
     }
 
     fn FSub(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFSub(B, LHS, RHS, _str.buf(""));
     }
 
     fn Mul(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildMul(B, LHS, RHS, _str.buf(""));
     }
 
     fn NSWMul(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNSWMul(B, LHS, RHS, _str.buf(""));
     }
 
     fn NUWMul(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNUWMul(B, LHS, RHS, _str.buf(""));
     }
 
     fn FMul(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFMul(B, LHS, RHS, _str.buf(""));
     }
 
     fn UDiv(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildUDiv(B, LHS, RHS, _str.buf(""));
     }
 
     fn SDiv(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildSDiv(B, LHS, RHS, _str.buf(""));
     }
 
     fn ExactSDiv(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildExactSDiv(B, LHS, RHS, _str.buf(""));
     }
 
     fn FDiv(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFDiv(B, LHS, RHS, _str.buf(""));
     }
 
     fn URem(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildURem(B, LHS, RHS, _str.buf(""));
     }
 
     fn SRem(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildSRem(B, LHS, RHS, _str.buf(""));
     }
 
     fn FRem(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFRem(B, LHS, RHS, _str.buf(""));
     }
 
     fn Shl(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildShl(B, LHS, RHS, _str.buf(""));
     }
 
     fn LShr(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildLShr(B, LHS, RHS, _str.buf(""));
     }
 
     fn AShr(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildAShr(B, LHS, RHS, _str.buf(""));
     }
 
     fn And(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildAnd(B, LHS, RHS, _str.buf(""));
     }
 
     fn Or(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildOr(B, LHS, RHS, _str.buf(""));
     }
 
     fn Xor(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildXor(B, LHS, RHS, _str.buf(""));
     }
 
     fn BinOp(Opcode Op, ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildBinOp(B, Op, LHS, RHS, _str.buf(""));
     }
 
     fn Neg(ValueRef V) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNeg(B, V, _str.buf(""));
     }
 
     fn NSWNeg(ValueRef V) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNSWNeg(B, V, _str.buf(""));
     }
 
     fn NUWNeg(ValueRef V) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNUWNeg(B, V, _str.buf(""));
     }
     fn FNeg(ValueRef V) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFNeg(B, V, _str.buf(""));
     }
     fn Not(ValueRef V) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildNot(B, V, _str.buf(""));
     }
 
     /* Memory */
     fn Malloc(TypeRef Ty) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildMalloc(B, Ty, _str.buf(""));
     }
 
     fn ArrayMalloc(TypeRef Ty, ValueRef Val) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildArrayMalloc(B, Ty, Val, _str.buf(""));
     }
 
     fn Alloca(TypeRef Ty) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildAlloca(B, Ty, _str.buf(""));
     }
 
     fn ArrayAlloca(TypeRef Ty, ValueRef Val) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildArrayAlloca(B, Ty, Val, _str.buf(""));
     }
 
     fn Free(ValueRef PointerVal) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFree(B, PointerVal);
     }
 
     fn Load(ValueRef PointerVal) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildLoad(B, PointerVal, _str.buf(""));
     }
 
     fn Store(ValueRef Val, ValueRef Ptr) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildStore(B, Val, Ptr);
     }
 
     fn GEP(ValueRef Pointer, vec[ValueRef] Indices) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildGEP(B, Pointer,
                               _vec.buf[ValueRef](Indices),
                               _vec.len[ValueRef](Indices),
@@ -1129,7 +1129,7 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     }
 
     fn InBoundsGEP(ValueRef Pointer, vec[ValueRef] Indices) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildInBoundsGEP(B, Pointer,
                                       _vec.buf[ValueRef](Indices),
                                       _vec.len[ValueRef](Indices),
@@ -1137,125 +1137,125 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     }
 
     fn StructGEP(ValueRef Pointer, uint Idx) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildStructGEP(B, Pointer, Idx, _str.buf(""));
     }
 
     fn GlobalString(sbuf Str) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildGlobalString(B, Str, _str.buf(""));
     }
 
     fn GlobalStringPtr(sbuf Str) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildGlobalStringPtr(B, Str, _str.buf(""));
     }
 
     /* Casts */
     fn Trunc(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildTrunc(B, Val, DestTy, _str.buf(""));
     }
 
     fn ZExt(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildZExt(B, Val, DestTy, _str.buf(""));
     }
 
     fn SExt(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildSExt(B, Val, DestTy, _str.buf(""));
     }
 
     fn FPToUI(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFPToUI(B, Val, DestTy, _str.buf(""));
     }
 
     fn FPToSI(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFPToSI(B, Val, DestTy, _str.buf(""));
     }
 
     fn UIToFP(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildUIToFP(B, Val, DestTy, _str.buf(""));
     }
 
     fn SIToFP(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildSIToFP(B, Val, DestTy, _str.buf(""));
     }
 
     fn FPTrunc(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFPTrunc(B, Val, DestTy, _str.buf(""));
     }
 
     fn FPExt(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFPExt(B, Val, DestTy, _str.buf(""));
     }
 
     fn PtrToInt(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildPtrToInt(B, Val, DestTy, _str.buf(""));
     }
 
     fn IntToPtr(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildIntToPtr(B, Val, DestTy, _str.buf(""));
     }
 
     fn BitCast(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildBitCast(B, Val, DestTy, _str.buf(""));
     }
 
     fn ZExtOrBitCast(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildZExtOrBitCast(B, Val, DestTy, _str.buf(""));
     }
 
     fn SExtOrBitCast(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildSExtOrBitCast(B, Val, DestTy, _str.buf(""));
     }
 
     fn TruncOrBitCast(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildTruncOrBitCast(B, Val, DestTy, _str.buf(""));
     }
 
     fn Cast(Opcode Op, ValueRef Val, TypeRef DestTy, sbuf Name) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildCast(B, Op, Val, DestTy, _str.buf(""));
     }
 
     fn PointerCast(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildPointerCast(B, Val, DestTy, _str.buf(""));
     }
 
     fn IntCast(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildIntCast(B, Val, DestTy, _str.buf(""));
     }
 
     fn FPCast(ValueRef Val, TypeRef DestTy) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFPCast(B, Val, DestTy, _str.buf(""));
     }
 
 
     /* Comparisons */
     fn ICmp(uint Op, ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildICmp(B, Op, LHS, RHS, _str.buf(""));
     }
 
     fn FCmp(uint Op, ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildFCmp(B, Op, LHS, RHS, _str.buf(""));
     }
 
@@ -1263,9 +1263,9 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     /* Miscellaneous instructions */
     fn Phi(TypeRef Ty, vec[ValueRef] vals,
            vec[BasicBlockRef] bbs) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         auto phi = llvm.LLVMBuildPhi(B, Ty, _str.buf(""));
-        check (_vec.len[ValueRef](vals) == _vec.len[BasicBlockRef](bbs));
+        assert (_vec.len[ValueRef](vals) == _vec.len[BasicBlockRef](bbs));
         llvm.LLVMAddIncoming(phi,
                              _vec.buf[ValueRef](vals),
                              _vec.buf[BasicBlockRef](bbs),
@@ -1276,7 +1276,7 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     fn AddIncomingToPhi(ValueRef phi,
                         vec[ValueRef] vals,
                         vec[BasicBlockRef] bbs) {
-        check (_vec.len[ValueRef](vals) == _vec.len[BasicBlockRef](bbs));
+        assert (_vec.len[ValueRef](vals) == _vec.len[BasicBlockRef](bbs));
         llvm.LLVMAddIncoming(phi,
                              _vec.buf[ValueRef](vals),
                              _vec.buf[BasicBlockRef](bbs),
@@ -1284,7 +1284,7 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     }
 
     fn Call(ValueRef Fn, vec[ValueRef] Args) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildCall(B, Fn,
                                _vec.buf[ValueRef](Args),
                                _vec.len[ValueRef](Args),
@@ -1292,7 +1292,7 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     }
 
     fn FastCall(ValueRef Fn, vec[ValueRef] Args) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         auto v = llvm.LLVMBuildCall(B, Fn,
                                     _vec.buf[ValueRef](Args),
                                     _vec.len[ValueRef](Args),
@@ -1302,65 +1302,65 @@ obj builder(BuilderRef B, @mutable bool terminated) {
     }
 
     fn Select(ValueRef If, ValueRef Then, ValueRef Else) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildSelect(B, If, Then, Else, _str.buf(""));
     }
 
     fn VAArg(ValueRef List, TypeRef Ty) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildVAArg(B, List, Ty, _str.buf(""));
     }
 
     fn ExtractElement(ValueRef VecVal, ValueRef Index) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildExtractElement(B, VecVal, Index, _str.buf(""));
     }
 
     fn InsertElement(ValueRef VecVal, ValueRef EltVal,
                      ValueRef Index) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildInsertElement(B, VecVal, EltVal, Index,
                                         _str.buf(""));
     }
 
     fn ShuffleVector(ValueRef V1, ValueRef V2, ValueRef Mask) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildShuffleVector(B, V1, V2, Mask, _str.buf(""));
     }
 
     fn ExtractValue(ValueRef AggVal, uint Index) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildExtractValue(B, AggVal, Index, _str.buf(""));
     }
 
     fn InsertValue(ValueRef AggVal, ValueRef EltVal,
                    uint Index) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildInsertValue(B, AggVal, EltVal, Index, _str.buf(""));
     }
 
     fn IsNull(ValueRef Val) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildIsNull(B, Val, _str.buf(""));
     }
 
     fn IsNotNull(ValueRef Val) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildIsNotNull(B, Val, _str.buf(""));
     }
 
     fn PtrDiff(ValueRef LHS, ValueRef RHS) -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         ret llvm.LLVMBuildPtrDiff(B, LHS, RHS, _str.buf(""));
     }
 
     fn Trap() -> ValueRef {
-        check (!*terminated);
+        assert (!*terminated);
         let BasicBlockRef BB = llvm.LLVMGetInsertBlock(B);
         let ValueRef FN = llvm.LLVMGetBasicBlockParent(BB);
         let ModuleRef M = llvm.LLVMGetGlobalParent(FN);
         let ValueRef T = llvm.LLVMGetNamedFunction(M, _str.buf("llvm.trap"));
-        check (T as int != 0);
+        assert (T as int != 0);
         let vec[ValueRef] Args = vec();
         ret llvm.LLVMBuildCall(B, T,
                                _vec.buf[ValueRef](Args),
@@ -1391,8 +1391,8 @@ state obj type_names(std.map.hashmap[TypeRef, str] type_names,
                     std.map.hashmap[str, TypeRef] named_types) {
 
     fn associate(str s, TypeRef t) {
-        check (!named_types.contains_key(s));
-        check (!type_names.contains_key(t));
+        assert (!named_types.contains_key(s));
+        assert (!type_names.contains_key(t));
         type_names.insert(t, s);
         named_types.insert(s, t);
     }

src/comp/middle/fold.rs

@@ -196,7 +196,10 @@ type ast_fold[ENV] =
          @expr e, ann a) -> @expr)                fold_expr_log,
 
      (fn(&ENV e, &span sp,
-         @expr e, ann a) -> @expr)                fold_expr_check_expr,
+         @expr e, ann a) -> @expr)                fold_expr_check,
+
+     (fn(&ENV e, &span sp,
+         @expr e, ann a) -> @expr)                fold_expr_assert,
 
      (fn(&ENV e, &span sp,
          ann a) -> @expr)                         fold_expr_port,
@@ -796,10 +799,16 @@ fn fold_expr[ENV](&ENV env, ast_fold[ENV] fld, &@expr e) -> @expr {
             ret fld.fold_expr_log(env_, e.span, l, ee, t2);
         }
 
-        case (ast.expr_check_expr(?x, ?t)) {
+        case (ast.expr_check(?x, ?t)) {
             auto ee = fold_expr(env_, fld, x);
             auto t2 = fld.fold_ann(env_, t);
-            ret fld.fold_expr_check_expr(env_, e.span, ee, t2);
+            ret fld.fold_expr_check(env_, e.span, ee, t2);
+        }
+
+        case (ast.expr_assert(?x, ?t)) {
+            auto ee = fold_expr(env_, fld, x);
+            auto t2 = fld.fold_ann(env_, t);
+            ret fld.fold_expr_assert(env_, e.span, ee, t2);
         }
 
         case (ast.expr_port(?t)) {
@@ -1380,9 +1389,14 @@ fn identity_fold_expr_log[ENV](&ENV e, &span sp, int lvl, @expr x,
     ret @respan(sp, ast.expr_log(lvl, x, a));
 }
 
-fn identity_fold_expr_check_expr[ENV](&ENV e, &span sp, @expr x, ann a)
+fn identity_fold_expr_check[ENV](&ENV e, &span sp, @expr x, ann a)
     -> @expr {
-    ret @respan(sp, ast.expr_check_expr(x, a));
+    ret @respan(sp, ast.expr_check(x, a));
+}
+
+fn identity_fold_expr_assert[ENV](&ENV e, &span sp, @expr x, ann a)
+    -> @expr {
+    ret @respan(sp, ast.expr_check(x, a));
 }
 
 fn identity_fold_expr_port[ENV](&ENV e, &span sp, ann a) -> @expr {
@@ -1676,8 +1690,11 @@ fn new_identity_fold[ENV]() -> ast_fold[ENV] {
          fold_expr_put    = bind identity_fold_expr_put[ENV](_,_,_,_),
          fold_expr_be     = bind identity_fold_expr_be[ENV](_,_,_,_),
          fold_expr_log    = bind identity_fold_expr_log[ENV](_,_,_,_,_),
-         fold_expr_check_expr
-         = bind identity_fold_expr_check_expr[ENV](_,_,_,_),
+         fold_expr_check
+         = bind identity_fold_expr_check[ENV](_,_,_,_),
+         fold_expr_assert
+         = bind identity_fold_expr_assert[ENV](_,_,_,_),
+              
          fold_expr_port   = bind identity_fold_expr_port[ENV](_,_,_),
          fold_expr_chan   = bind identity_fold_expr_chan[ENV](_,_,_,_),
 

src/comp/middle/metadata.rs

@@ -63,7 +63,7 @@ mod Encode {
     );
 
     fn ty_str(@ctxt cx, ty.t t) -> str {
-        check (! cx.use_abbrevs);
+        assert (! cx.use_abbrevs);
         auto sw = io.string_writer();
         enc_ty(sw.get_writer(), cx, t);
         ret sw.get_str();

src/comp/middle/resolve.rs

@@ -662,7 +662,7 @@ fn fold_pat_tag(&env e, &span sp, ast.path p, vec[@ast.pat] args,
 fn fold_expr_path(&env e, &span sp, &ast.path p, &option.t[def] d,
                   ann a) -> @ast.expr {
     auto n_idents = _vec.len[ast.ident](p.node.idents);
-    check (n_idents != 0u);
+    assert (n_idents != 0u);
 
     auto index = new_def_hash[def_wrap]();
     auto d = find_final_def(e, index, sp, p.node.idents, ns_value,

src/comp/middle/trans.rs

@@ -592,7 +592,7 @@ fn type_of_explicit_args(@crate_ctxt cx, vec[ty.arg] inputs) -> vec[TypeRef] {
     let vec[TypeRef] atys = vec();
     for (ty.arg arg in inputs) {
         if (ty.type_has_dynamic_size(cx.tcx, arg.ty)) {
-            check (arg.mode == ast.alias);
+            assert (arg.mode == ast.alias);
             atys += vec(T_typaram_ptr(cx.tn));
         } else {
             let TypeRef t;
@@ -638,7 +638,7 @@ fn type_of_fn_full(@crate_ctxt cx,
     // Arg 2: Env (closure-bindings / self-obj)
     alt (obj_self) {
         case (some[TypeRef](?t)) {
-            check (t as int != 0);
+            assert (t as int != 0);
             atys += vec(t);
         }
         case (_) {
@@ -806,7 +806,7 @@ fn type_of_inner(@crate_ctxt cx, ty.t t) -> TypeRef {
         case (ty.ty_type) { llty = T_ptr(T_tydesc(cx.tn)); }
     }
 
-    check (llty as int != 0);
+    assert (llty as int != 0);
     llvm.LLVMAddTypeName(cx.llmod,
                          _str.buf(ty.ty_to_short_str(cx.tcx,
                                                      cx.type_abbrevs, t)),
@@ -1361,7 +1361,7 @@ fn dynamic_align_of(@block_ctxt cx, ty.t t) -> result {
 fn GEP_tup_like(@block_ctxt cx, ty.t t,
                 ValueRef base, vec[int] ixs) -> result {
 
-    check (ty.type_is_tup_like(cx.fcx.lcx.ccx.tcx, t));
+    assert (ty.type_is_tup_like(cx.fcx.lcx.ccx.tcx, t));
 
     // It might be a static-known type. Handle this.
 
@@ -1399,17 +1399,17 @@ fn GEP_tup_like(@block_ctxt cx, ty.t t,
         // and the latter would only be meaningful if we supported non-0
         // values for the 0th index (we don't).
 
-        check (len > 1u);
+        assert (len > 1u);
 
         if (n == 0u) {
             // Since we're starting from a value that's a pointer to a
             // *single* structure, the first index (in GEP-ese) should just be
             // 0, to yield the pointee.
-            check (ixs.(n) == 0);
+            assert (ixs.(n) == 0);
             ret split_type(ccx, t, ixs, n+1u);
         }
 
-        check (n < len);
+        assert (n < len);
 
         let int ix = ixs.(n);
         let vec[ty.t] prefix = vec();
@@ -1603,8 +1603,8 @@ fn get_tydesc(&@block_ctxt cx, ty.t t, bool escapes) -> result {
         let uint n_params = ty.count_ty_params(cx.fcx.lcx.ccx.tcx, t);
         auto tys = linearize_ty_params(cx, t);
 
-        check (n_params == _vec.len[uint](tys._0));
-        check (n_params == _vec.len[ValueRef](tys._1));
+        assert (n_params == _vec.len[uint](tys._0));
+        assert (n_params == _vec.len[ValueRef](tys._1));
 
         auto root = get_static_tydesc(cx, t, tys._0).tydesc;
 
@@ -2327,7 +2327,7 @@ fn tag_variants(@crate_ctxt cx, ast.def_id id) -> vec[variant_info] {
         ret creader.get_tag_variants(cx.sess, cx.tcx, id);
     }
 
-    check (cx.items.contains_key(id));
+    assert (cx.items.contains_key(id));
     alt (cx.items.get(id).node) {
         case (ast.item_tag(_, ?variants, _, _, _)) {
             let vec[variant_info] result = vec();
@@ -3346,7 +3346,7 @@ fn join_results(@block_ctxt parent_cx,
             // No incoming edges are live, so we're in dead-code-land.
             // Arbitrarily pick the first dead edge, since the caller
             // is just going to propagate it outward.
-            check (_vec.len[result](ins) >= 1u);
+            assert (_vec.len[result](ins) >= 1u);
             ret ins.(0);
         }
 
@@ -3974,7 +3974,7 @@ fn lval_generic_fn(@block_ctxt cx,
     auto lv;
     if (cx.fcx.lcx.ccx.sess.get_targ_crate_num() == fn_id._0) {
         // Internal reference.
-        check (cx.fcx.lcx.ccx.fn_pairs.contains_key(fn_id));
+        assert (cx.fcx.lcx.ccx.fn_pairs.contains_key(fn_id));
         lv = lval_val(cx, cx.fcx.lcx.ccx.fn_pairs.get(fn_id));
     } else {
         // External reference.
@@ -4017,7 +4017,7 @@ fn lookup_discriminant(@local_ctxt lcx, ast.def_id tid, ast.def_id vid)
     alt (lcx.ccx.discrims.find(vid)) {
         case (none[ValueRef]) {
             // It's an external discriminant that we haven't seen yet.
-            check (lcx.ccx.sess.get_targ_crate_num() != vid._0);
+            assert (lcx.ccx.sess.get_targ_crate_num() != vid._0);
             auto sym = creader.get_symbol(lcx.ccx.sess, vid);
             auto gvar = llvm.LLVMAddGlobal(lcx.ccx.llmod, T_int(),
                                            _str.buf(sym));
@@ -4039,7 +4039,7 @@ fn trans_path(@block_ctxt cx, &ast.path p, &option.t[ast.def] dopt,
                 case (ast.def_arg(?did)) {
                     alt (cx.fcx.llargs.find(did)) {
                         case (none[ValueRef]) {
-                            check (cx.fcx.llupvars.contains_key(did));
+                            assert (cx.fcx.llupvars.contains_key(did));
                             ret lval_mem(cx, cx.fcx.llupvars.get(did));
                         }
                         case (some[ValueRef](?llval)) {
@@ -4050,7 +4050,7 @@ fn trans_path(@block_ctxt cx, &ast.path p, &option.t[ast.def] dopt,
                 case (ast.def_local(?did)) {
                     alt (cx.fcx.lllocals.find(did)) {
                         case (none[ValueRef]) {
-                            check (cx.fcx.llupvars.contains_key(did));
+                            assert (cx.fcx.llupvars.contains_key(did));
                             ret lval_mem(cx, cx.fcx.llupvars.get(did));
                         }
                         case (some[ValueRef](?llval)) {
@@ -4059,11 +4059,11 @@ fn trans_path(@block_ctxt cx, &ast.path p, &option.t[ast.def] dopt,
                     }
                 }
                 case (ast.def_binding(?did)) {
-                    check (cx.fcx.lllocals.contains_key(did));
+                    assert (cx.fcx.lllocals.contains_key(did));
                     ret lval_mem(cx, cx.fcx.lllocals.get(did));
                 }
                 case (ast.def_obj_field(?did)) {
-                    check (cx.fcx.llobjfields.contains_key(did));
+                    assert (cx.fcx.llobjfields.contains_key(did));
                     ret lval_mem(cx, cx.fcx.llobjfields.get(did));
                 }
                 case (ast.def_fn(?did)) {
@@ -4115,7 +4115,7 @@ fn trans_path(@block_ctxt cx, &ast.path p, &option.t[ast.def] dopt,
                 }
                 case (ast.def_const(?did)) {
                     // TODO: externals
-                    check (cx.fcx.lcx.ccx.consts.contains_key(did));
+                    assert (cx.fcx.lcx.ccx.consts.contains_key(did));
                     ret lval_mem(cx, cx.fcx.lcx.ccx.consts.get(did));
                 }
                 case (ast.def_native_fn(?did)) {
@@ -4254,7 +4254,7 @@ fn trans_lval(@block_ctxt cx, @ast.expr e) -> lval_result {
             ret trans_index(cx, e.span, base, idx, ann);
         }
         case (ast.expr_unary(?unop, ?base, ?ann)) {
-            check (unop == ast.deref);
+            assert (unop == ast.deref);
 
             auto sub = trans_expr(cx, base);
             auto val = sub.bcx.build.GEP(sub.val,
@@ -4418,7 +4418,7 @@ fn trans_bind_thunk(@local_ctxt cx,
                     }
                 } else if (ty.type_contains_params(cx.ccx.tcx,
                                                    out_arg.ty)) {
-                    check (out_arg.mode == ast.alias);
+                    assert (out_arg.mode == ast.alias);
                     val = bcx.build.PointerCast(val, llout_arg_ty);
                 }
 
@@ -4431,7 +4431,7 @@ fn trans_bind_thunk(@local_ctxt cx,
                 let ValueRef passed_arg = llvm.LLVMGetParam(llthunk, a);
 
                 if (ty.type_contains_params(cx.ccx.tcx, out_arg.ty)) {
-                    check (out_arg.mode == ast.alias);
+                    assert (out_arg.mode == ast.alias);
                     passed_arg = bcx.build.PointerCast(passed_arg,
                                                        llout_arg_ty);
                 }
@@ -5121,7 +5121,7 @@ fn trans_expr(@block_ctxt cx, @ast.expr e) -> result {
 
         case (ast.expr_assign(?dst, ?src, ?ann)) {
             auto lhs_res = trans_lval(cx, dst);
-            check (lhs_res.is_mem);
+            assert (lhs_res.is_mem);
             auto rhs_res = trans_expr(lhs_res.res.bcx, src);
             auto t = node_ann_type(cx.fcx.lcx.ccx, ann);
             // FIXME: calculate copy init-ness in typestate.
@@ -5132,7 +5132,7 @@ fn trans_expr(@block_ctxt cx, @ast.expr e) -> result {
         case (ast.expr_assign_op(?op, ?dst, ?src, ?ann)) {
             auto t = node_ann_type(cx.fcx.lcx.ccx, ann);
             auto lhs_res = trans_lval(cx, dst);
-            check (lhs_res.is_mem);
+            assert (lhs_res.is_mem);
             auto rhs_res = trans_expr(lhs_res.res.bcx, src);
             if (ty.type_is_sequence(cx.fcx.lcx.ccx.tcx, t)) {
                 alt (op) {
@@ -5189,7 +5189,11 @@ fn trans_expr(@block_ctxt cx, @ast.expr e) -> result {
             ret trans_log(lvl, cx, a);
         }
 
-        case (ast.expr_check_expr(?a, _)) {
+        case (ast.expr_assert(?a, _)) {
+            ret trans_check_expr(cx, a);
+        }
+
+        case (ast.expr_check(?a, _)) {
             ret trans_check_expr(cx, a);
         }
 
@@ -5510,7 +5514,7 @@ fn trans_ret(@block_ctxt cx, &option.t[@ast.expr] e) -> result {
 
 fn trans_be(@block_ctxt cx, @ast.expr e) -> result {
     // FIXME: This should be a typestate precondition
-    check (ast.is_call_expr(e));
+    assert (ast.is_call_expr(e));
     // FIXME: Turn this into a real tail call once
     // calling convention issues are settled
     ret trans_ret(cx, some(e));
@@ -5606,7 +5610,7 @@ fn trans_recv(@block_ctxt cx, @ast.expr lhs, @ast.expr rhs,
 
     auto bcx = cx;
     auto data = trans_lval(bcx, lhs);
-    check (data.is_mem);
+    assert (data.is_mem);
     bcx = data.res.bcx;
     auto unit_ty = node_ann_type(bcx.fcx.lcx.ccx, ann);
 
@@ -5638,7 +5642,7 @@ fn recv_val(@block_ctxt cx, ValueRef lhs, @ast.expr rhs,
 fn init_local(@block_ctxt cx, @ast.local local) -> result {
 
     // Make a note to drop this slot on the way out.
-    check (cx.fcx.lllocals.contains_key(local.id));
+    assert (cx.fcx.lllocals.contains_key(local.id));
     auto llptr = cx.fcx.lllocals.get(local.id);
     auto ty = node_ann_type(cx.fcx.lcx.ccx, local.ann);
     auto bcx = cx;
@@ -5754,7 +5758,7 @@ fn trans_block_cleanups(@block_ctxt cx,
     auto bcx = cx;
 
     if (cleanup_cx.kind == NON_SCOPE_BLOCK) {
-        check (_vec.len[cleanup](cleanup_cx.cleanups) == 0u);
+        assert (_vec.len[cleanup](cleanup_cx.cleanups) == 0u);
     }
 
     auto i = _vec.len[cleanup](cleanup_cx.cleanups);
@@ -5975,7 +5979,7 @@ fn create_llargs_for_fn_args(&@fn_ctxt cx,
             auto i = 0u;
             for (ast.ty_param tp in ty_params) {
                 auto llarg = llvm.LLVMGetParam(cx.llfn, arg_n);
-                check (llarg as int != 0);
+                assert (llarg as int != 0);
                 cx.lltydescs += vec(llarg);
                 arg_n += 1u;
                 i += 1u;
@@ -5985,14 +5989,14 @@ fn create_llargs_for_fn_args(&@fn_ctxt cx,
 
     if (proto == ast.proto_iter) {
         auto llarg = llvm.LLVMGetParam(cx.llfn, arg_n);
-        check (llarg as int != 0);
+        assert (llarg as int != 0);
         cx.lliterbody = some[ValueRef](llarg);
         arg_n += 1u;
     }
 
     for (ast.arg arg in args) {
         auto llarg = llvm.LLVMGetParam(cx.llfn, arg_n);
-        check (llarg as int != 0);
+        assert (llarg as int != 0);
         cx.llargs.insert(arg.id, llarg);
         arg_n += 1u;
     }
@@ -6430,7 +6434,7 @@ fn trans_tag_variant(@local_ctxt cx, ast.def_id tag_id,
                            id=varg.id));
     }
 
-    check (cx.ccx.item_ids.contains_key(variant.node.id));
+    assert (cx.ccx.item_ids.contains_key(variant.node.id));
     let ValueRef llfndecl = cx.ccx.item_ids.get(variant.node.id);
 
     auto fcx = new_fn_ctxt(cx, llfndecl);
@@ -6697,7 +6701,7 @@ fn decl_native_fn_and_pair(@crate_ctxt ccx,
             for each (uint i in _uint.range(0u, num_ty_param)) {
                 auto llarg = llvm.LLVMGetParam(fcx.llfn, arg_n);
                 fcx.lltydescs += vec(llarg);
-                check (llarg as int != 0);
+                assert (llarg as int != 0);
                 call_args += vec(vp2i(bcx, llarg));
                 arg_n += 1u;
             }
@@ -6763,7 +6767,7 @@ fn decl_native_fn_and_pair(@crate_ctxt ccx,
 
         for (ty.arg arg in args) {
             auto llarg = llvm.LLVMGetParam(fcx.llfn, arg_n);
-            check (llarg as int != 0);
+            assert (llarg as int != 0);
             push_arg(bcx, call_args, llarg, arg.ty, arg.mode);
             if (arg.mode == ast.val) {
                 drop_args += vec(tup(llarg, arg.ty));

src/comp/middle/ty.rs

@@ -895,7 +895,7 @@ fn type_is_tup_like(ctxt cx, t ty) -> bool {
 }
 
 fn get_element_type(ctxt cx, t ty, uint i) -> t {
-    check (type_is_tup_like(cx, ty));
+    assert (type_is_tup_like(cx, ty));
     alt (struct(cx, ty)) {
         case (ty_tup(?mts)) {
             ret mts.(i).ty;
@@ -1785,50 +1785,117 @@ fn pat_ty(ctxt cx, @ast.pat pat) -> t {
     fail;   // not reached
 }
 
-fn expr_ann(@ast.expr expr) -> option.t[ast.ann] {
-    alt (expr.node) {
-        case (ast.expr_vec(_, _, ?ann))       { ret some[ast.ann](ann); }
-        case (ast.expr_tup(_, ?ann))          { ret some[ast.ann](ann); }
-        case (ast.expr_rec(_, _, ?ann))       { ret some[ast.ann](ann); }
-        case (ast.expr_bind(_, _, ?ann))      { ret some[ast.ann](ann); }
-        case (ast.expr_call(_, _, ?ann))      { ret some[ast.ann](ann); }
-        case (ast.expr_self_method(_, ?ann))  { ret some[ast.ann](ann); }
-        case (ast.expr_spawn(_, _, _, _, ?ann))
-                                              { ret some[ast.ann](ann); }
-        case (ast.expr_binary(_, _, _, ?ann)) { ret some[ast.ann](ann); }
-        case (ast.expr_unary(_, _, ?ann))     { ret some[ast.ann](ann); }
-        case (ast.expr_lit(_, ?ann))          { ret some[ast.ann](ann); }
-        case (ast.expr_cast(_, _, ?ann))      { ret some[ast.ann](ann); }
-        case (ast.expr_if(_, _, _, ?ann))     { ret some[ast.ann](ann); }
-        case (ast.expr_for(_, _, _, ?ann))    { ret some[ast.ann](ann); }
-        case (ast.expr_for_each(_, _, _, ?ann))
-                                              { ret some[ast.ann](ann); }
-        case (ast.expr_while(_, _, ?ann))     { ret some[ast.ann](ann); }
-        case (ast.expr_do_while(_, _, ?ann))  { ret some[ast.ann](ann); }
-        case (ast.expr_alt(_, _, ?ann))       { ret some[ast.ann](ann); }
-        case (ast.expr_block(_, ?ann))        { ret some[ast.ann](ann); }
-        case (ast.expr_assign(_, _, ?ann))    { ret some[ast.ann](ann); }
-        case (ast.expr_assign_op(_, _, _, ?ann))
-                                              { ret some[ast.ann](ann); }
-        case (ast.expr_field(_, _, ?ann))     { ret some[ast.ann](ann); }
-        case (ast.expr_index(_, _, ?ann))     { ret some[ast.ann](ann); }
-        case (ast.expr_path(_, _, ?ann))      { ret some[ast.ann](ann); }
-        case (ast.expr_ext(_, _, _, _, ?ann)) { ret some[ast.ann](ann); }
-        case (ast.expr_port(?ann))            { ret some[ast.ann](ann); }
-        case (ast.expr_chan(_, ?ann))         { ret some[ast.ann](ann); }
-        case (ast.expr_send(_, _, ?ann))      { ret some[ast.ann](ann); }
-        case (ast.expr_recv(_, _, ?ann))      { ret some[ast.ann](ann); }
-
-        case (ast.expr_fail(_))               { ret none[ast.ann]; }
-        case (ast.expr_break(_))              { ret none[ast.ann]; }
-        case (ast.expr_cont(_))               { ret none[ast.ann]; }
-        case (ast.expr_log(_,_,_))            { ret none[ast.ann]; }
-        case (ast.expr_check_expr(_,_))       { ret none[ast.ann]; }
-        case (ast.expr_ret(_,_))              { ret none[ast.ann]; }
-        case (ast.expr_put(_,_))              { ret none[ast.ann]; }
-        case (ast.expr_be(_,_))               { ret none[ast.ann]; }
+fn expr_ann(&@ast.expr e) -> ast.ann {
+    alt(e.node) {
+        case (ast.expr_vec(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_tup(_,?a)) {
+            ret a;
+        }
+        case (ast.expr_rec(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_call(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_bind(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_binary(_,_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_unary(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_lit(_,?a)) {
+            ret a;
+        }
+        case (ast.expr_cast(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_if(_,_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_while(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_for(_,_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_for_each(_,_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_do_while(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_alt(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_block(_,?a)) {
+            ret a;
+        }
+        case (ast.expr_assign(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_assign_op(_,_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_send(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_recv(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_field(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_index(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_path(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_ext(_,_,_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_fail(?a)) {
+            ret a;
+        }
+        case (ast.expr_ret(_,?a)) {
+            ret a; 
+        }
+        case (ast.expr_put(_,?a)) {
+            ret a;
+        }
+        case (ast.expr_be(_,?a)) {
+            ret a;
+        }
+        case (ast.expr_log(_,_,?a)) {
+            ret a;
+        }
+        case (ast.expr_assert(_,?a)) {
+            ret a;
+        }
+        case (ast.expr_check(_,?a)) {
+            ret a;
+        }
+        case (ast.expr_port(?a)) {
+            ret a;
+        }
+        case (ast.expr_chan(_,?a)) {
+            ret a;
+        }
+        case (ast.expr_break(?a)) {
+            ret a;
+        }
+        case (ast.expr_cont(?a)) {
+            ret a;
+        }
+        case (ast.expr_self_method(_, ?a)) {
+            ret a;
+        }
     }
-    fail;
 }
 
 // Returns the type of an expression as a monotype.
@@ -1838,35 +1905,21 @@ fn expr_ann(@ast.expr expr) -> option.t[ast.ann] {
 // instead of "fn(&T) -> T with T = int". If this isn't what you want, see
 // expr_ty_params_and_ty() below.
 fn expr_ty(ctxt cx, @ast.expr expr) -> t {
-    alt (expr_ann(expr)) {
-        case (none[ast.ann])     { ret mk_nil(cx); }
-        case (some[ast.ann](?a)) { ret ann_to_monotype(cx, a); }
-    }
+    { ret ann_to_monotype(cx, expr_ann(expr)); }
 }
 
 fn expr_ty_params_and_ty(ctxt cx, @ast.expr expr) -> tup(vec[t], t) {
-    alt (expr_ann(expr)) {
-        case (none[ast.ann]) {
-            let vec[t] tps = vec();
-            ret tup(tps, mk_nil(cx));
-        }
-        case (some[ast.ann](?a)) {
-            ret tup(ann_to_type_params(a), ann_to_type(a));
-        }
-    }
+    auto a = expr_ann(expr);
+
+    ret tup(ann_to_type_params(a), ann_to_type(a));
 }
 
 fn expr_has_ty_params(@ast.expr expr) -> bool {
     // FIXME: Rewrite using complex patterns when they're trustworthy.
     alt (expr_ann(expr)) {
-        case (none[ast.ann]) { fail; }
-        case (some[ast.ann](?a)) {
-            alt (a) {
-                case (ast.ann_none) { fail; }
-                case (ast.ann_type(_, ?tps_opt, _)) {
-                    ret !option.is_none[vec[t]](tps_opt);
-                }
-            }
+        case (ast.ann_none) { fail; }
+        case (ast.ann_type(_, ?tps_opt, _)) {
+            ret !option.is_none[vec[t]](tps_opt);
         }
     }
 }
@@ -2233,7 +2286,7 @@ mod Unify {
                         if (actual_n < vlen) {
                             cx.types.(actual_n) += vec(expected);
                         } else {
-                            check (actual_n == vlen);
+                            assert (actual_n == vlen);
                             cx.types += vec(mutable vec(expected));
                         }
                     }
@@ -2601,7 +2654,7 @@ mod Unify {
                 if (expected_n < vlen) {
                     cx.types.(expected_n) += vec(actual);
                 } else {
-                    check (expected_n == vlen);
+                    assert (expected_n == vlen);
                     cx.types += vec(mutable vec(actual));
                 }
                 ret ures_ok(expected);

src/comp/middle/typeck.rs

@@ -110,7 +110,7 @@ fn ty_param_count_and_ty_for_def(@fn_ctxt fcx, &ast.span sp, &ast.def defn)
         -> ty_param_count_and_ty {
     alt (defn) {
         case (ast.def_arg(?id)) {
-            // check (fcx.locals.contains_key(id));
+            // assert (fcx.locals.contains_key(id));
             ret tup(0u, fcx.locals.get(id));
         }
         case (ast.def_local(?id)) {
@@ -122,7 +122,7 @@ fn ty_param_count_and_ty_for_def(@fn_ctxt fcx, &ast.span sp, &ast.def defn)
             ret tup(0u, t);
         }
         case (ast.def_obj_field(?id)) {
-            // check (fcx.locals.contains_key(id));
+            // assert (fcx.locals.contains_key(id));
             ret tup(0u, fcx.locals.get(id));
         }
         case (ast.def_fn(?id)) {
@@ -142,7 +142,7 @@ fn ty_param_count_and_ty_for_def(@fn_ctxt fcx, &ast.span sp, &ast.def defn)
                                     fcx.ccx.type_cache, vid);
         }
         case (ast.def_binding(?id)) {
-            // check (fcx.locals.contains_key(id));
+            // assert (fcx.locals.contains_key(id));
             ret tup(0u, fcx.locals.get(id));
         }
         case (ast.def_obj(?id)) {
@@ -298,7 +298,7 @@ fn ast_ty_to_ty(ty.ctxt tcx, ty_getter getter, &@ast.ty ast_ty) -> ty.t {
         }
 
         case (ast.ty_path(?path, ?def)) {
-            check (def != none[ast.def]);
+            assert (def != none[ast.def]);
             alt (option.get[ast.def](def)) {
                 case (ast.def_ty(?id)) {
                     typ = instantiate(tcx, getter, id, path.node.types);
@@ -411,7 +411,7 @@ mod Collect {
             ret creader.get_type(cx.sess, cx.tcx, id);
         }
 
-        // check (cx.id_to_ty_item.contains_key(id));
+        // assert (cx.id_to_ty_item.contains_key(id));
 
         auto it = cx.id_to_ty_item.get(id);
         auto tpt;
@@ -672,7 +672,7 @@ mod Collect {
     fn fold_item_const(&@env e, &span sp, ast.ident i,
                        @ast.ty t, @ast.expr ex,
                        ast.def_id id, ast.ann a) -> @ast.item {
-        // check (e.cx.type_cache.contains_key(id));
+        // assert (e.cx.type_cache.contains_key(id));
         auto typ = e.cx.type_cache.get(id)._1;
         auto item = ast.item_const(i, t, ex, id, triv_ann(typ));
         ret @fold.respan[ast.item_](sp, item);
@@ -681,7 +681,7 @@ mod Collect {
     fn fold_item_fn(&@env e, &span sp, ast.ident i,
                     &ast._fn f, vec[ast.ty_param] ty_params,
                     ast.def_id id, ast.ann a) -> @ast.item {
-        // check (e.cx.type_cache.contains_key(id));
+        // assert (e.cx.type_cache.contains_key(id));
         auto typ = e.cx.type_cache.get(id)._1;
         auto item = ast.item_fn(i, f, ty_params, id, triv_ann(typ));
         ret @fold.respan[ast.item_](sp, item);
@@ -690,7 +690,7 @@ mod Collect {
     fn fold_native_item_fn(&@env e, &span sp, ast.ident i, option.t[str] ln,
                            &ast.fn_decl d, vec[ast.ty_param] ty_params,
                            ast.def_id id, ast.ann a) -> @ast.native_item {
-        // check (e.cx.type_cache.contains_key(id));
+        // assert (e.cx.type_cache.contains_key(id));
         auto typ = e.cx.type_cache.get(id)._1;
         auto item = ast.native_item_fn(i, ln, d, ty_params, id,
                                        triv_ann(typ));
@@ -721,7 +721,7 @@ mod Collect {
     fn fold_item_obj(&@env e, &span sp, ast.ident i,
                     &ast._obj ob, vec[ast.ty_param] ty_params,
                     ast.obj_def_ids odid, ast.ann a) -> @ast.item {
-        // check (e.cx.type_cache.contains_key(odid.ctor));
+        // assert (e.cx.type_cache.contains_key(odid.ctor));
         auto t = e.cx.type_cache.get(odid.ctor)._1;
         let vec[method] meth_tys = get_ctor_obj_methods(e, t);
         let vec[@ast.method] methods = vec();
@@ -777,7 +777,7 @@ mod Collect {
     fn fold_item_ty(&@env e, &span sp, ast.ident i,
                     @ast.ty t, vec[ast.ty_param] ty_params,
                     ast.def_id id, ast.ann a) -> @ast.item {
-        // check (e.cx.type_cache.contains_key(id));
+        // assert (e.cx.type_cache.contains_key(id));
         auto typ = e.cx.type_cache.get(id)._1;
         auto item = ast.item_ty(i, t, ty_params, id, triv_ann(typ));
         ret @fold.respan[ast.item_](sp, item);
@@ -1214,7 +1214,7 @@ mod Pushdown {
                             case (none[@ast.expr]) {
                                 auto i = 0u;
                                 for (ast.field field_0 in fields_0) {
-                                    check (_str.eq(field_0.ident,
+                                    assert (_str.eq(field_0.ident,
                                                    field_mts.(i).ident));
                                     auto e_1 =
                                         pushdown_expr(fcx,
@@ -1409,7 +1409,8 @@ mod Pushdown {
             case (ast.expr_ret(_,_)) { e_1 = e.node; }
             case (ast.expr_put(_,_)) { e_1 = e.node; }
             case (ast.expr_be(_,_))  { e_1 = e.node; }
-            case (ast.expr_check_expr(_,_)) { e_1 = e.node; }
+            case (ast.expr_check(_,_)) { e_1 = e.node; }
+            case (ast.expr_assert(_,_)) { e_1 = e.node; }
 
             case (ast.expr_port(?ann)) {
                 auto t = Demand.simple(fcx, e.span, expected,
@@ -1839,7 +1840,7 @@ fn check_expr(&@fn_ctxt fcx, @ast.expr expr) -> @ast.expr {
 
         case (ast.expr_path(?pth, ?defopt, _)) {
             auto t = ty.mk_nil(fcx.ccx.tcx);
-            check (defopt != none[ast.def]);
+            assert (defopt != none[ast.def]);
             auto defn = option.get[ast.def](defopt);
 
             auto tpt = ty_param_count_and_ty_for_def(fcx, expr.span, defn);
@@ -1939,7 +1940,7 @@ fn check_expr(&@fn_ctxt fcx, @ast.expr expr) -> @ast.expr {
 
         case (ast.expr_be(?e, _)) {
             /* FIXME: prove instead of check */
-            check (ast.is_call_expr(e));
+            assert (ast.is_call_expr(e));
             auto expr_0 = check_expr(fcx, e);
             auto expr_1 = Pushdown.pushdown_expr(fcx, fcx.ret_ty, expr_0);
             ret @fold.respan[ast.expr_](expr.span,
@@ -1953,12 +1954,25 @@ fn check_expr(&@fn_ctxt fcx, @ast.expr expr) -> @ast.expr {
                                          plain_ann(fcx.ccx.tcx)));
         }
 
-        case (ast.expr_check_expr(?e, _)) {
+        case (ast.expr_check(?e, _)) {
+            /* FIXME */
+        /* presumably, here is where we should check that e is
+         actually a call to a predicate, where all the arguments
+        are literals or slot variables? */
             auto expr_t = check_expr(fcx, e);
             Demand.simple(fcx, expr.span, ty.mk_bool(fcx.ccx.tcx),
                           expr_ty(fcx.ccx.tcx, expr_t));
             ret @fold.respan[ast.expr_]
-                (expr.span, ast.expr_check_expr(expr_t,
+                (expr.span, ast.expr_check(expr_t,
+                                                plain_ann(fcx.ccx.tcx)));
+        }
+
+        case (ast.expr_assert(?e, _)) {
+            auto expr_t = check_expr(fcx, e);
+            Demand.simple(fcx, expr.span, ty.mk_bool(fcx.ccx.tcx),
+                          expr_ty(fcx.ccx.tcx, expr_t));
+            ret @fold.respan[ast.expr_]
+                (expr.span, ast.expr_assert(expr_t,
                                                 plain_ann(fcx.ccx.tcx)));
         }
 

src/comp/middle/typestate_check.rs

@@ -55,7 +55,8 @@ import front.ast.expr_put;
 import front.ast.expr_port;
 import front.ast.expr_chan;
 import front.ast.expr_be;
-import front.ast.expr_check_expr;
+import front.ast.expr_check;
+import front.ast.expr_assert;
 import front.ast.expr_cast;
 import front.ast.expr_for;
 import front.ast.expr_for_each;
@@ -147,8 +148,7 @@ import util.typestate_ann.clone;
 import middle.ty;
 import middle.ty.ann_to_type;
 import middle.ty.arg;
-import middle.ty.block_ty;
-import middle.ty.expr_ty;
+import middle.ty.expr_ann;
 import middle.ty.ty_to_str;
 
 import pretty.pprust.print_block;
@@ -293,11 +293,11 @@ type fn_info      = std.map.hashmap[def_id, var_info];
 type fn_info_map = std.map.hashmap[def_id, fn_info];
  
 fn bit_num(def_id v, fn_info m) -> uint {
-  check (m.contains_key(v));
+  assert (m.contains_key(v));
   ret m.get(v)._0;
 }
 fn get_fn_info(fn_info_map fm, def_id did) -> fn_info {
-    check (fm.contains_key(did));
+    assert (fm.contains_key(did));
     ret fm.get(did);
 }
 
@@ -389,116 +389,6 @@ fn mk_f_to_fn_info(@ast.crate c) -> fn_info_map {
   ret res;
 }
 /**** Helpers ****/
-fn expr_ann(&expr e) -> ann {
-  alt(e.node) {
-    case (ast.expr_vec(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_tup(_,?a)) {
-      ret a;
-    }
-    case (ast.expr_rec(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_call(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_bind(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_binary(_,_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_unary(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_lit(_,?a)) {
-      ret a;
-    }
-    case (ast.expr_cast(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_if(_,_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_while(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_for(_,_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_for_each(_,_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_do_while(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_alt(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_block(_,?a)) {
-      ret a;
-    }
-    case (ast.expr_assign(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_assign_op(_,_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_send(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_recv(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_field(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_index(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_path(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_ext(_,_,_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_fail(?a)) {
-      ret a;
-    }
-    case (ast.expr_ret(_,?a)) {
-      ret a; 
-    }
-    case (ast.expr_put(_,?a)) {
-      ret a;
-    }
-    case (ast.expr_be(_,?a)) {
-      ret a;
-    }
-    case (ast.expr_log(_,_,?a)) {
-      ret a;
-    }
-    case (ast.expr_check_expr(_,?a)) {
-      ret a;
-    }
-    case (ast.expr_port(?a)) {
-      ret a;
-    }
-    case (ast.expr_chan(_,?a)) {
-      ret a;
-    }
-    case (expr_break(?a)) {
-        ret a;
-    }
-    case (expr_cont(?a)) {
-        ret a;
-    }
-    case (expr_self_method(_, ?a)) {
-        ret a;
-    }
-  }
-}
-
 fn ann_to_ts_ann(ann a, uint nv) -> ts_ann {
   alt (a) {
     case (ann_none)         { ret empty_ann(nv); }
@@ -532,7 +422,7 @@ fn ann_to_ts_ann_fail_more(ann a) -> @ts_ann {
           fail;
       }
       case (ann_type(_,_,?t)) {
-          check (! is_none[@ts_ann](t));
+          assert (! is_none[@ts_ann](t));
           ret get[@ts_ann](t);
       }
   }
@@ -557,7 +447,7 @@ fn stmt_to_ann(&stmt s) -> option.t[@ts_ann] {
 }
 
 /* fails if e has no annotation */
-fn expr_states(&expr e) -> pre_and_post_state {
+fn expr_states(@expr e) -> pre_and_post_state {
   alt (expr_ann(e)) {
     case (ann_none) {
       log_err "expr_pp: the impossible happened (no annotation)";
@@ -578,7 +468,7 @@ fn expr_states(&expr e) -> pre_and_post_state {
 }
 
 /* fails if e has no annotation */
-fn expr_pp(&expr e) -> pre_and_post {
+fn expr_pp(@expr e) -> pre_and_post {
   alt (expr_ann(e)) {
     case (ann_none) {
       log_err "expr_pp: the impossible happened (no annotation)";
@@ -664,19 +554,19 @@ fn stmt_states(&stmt s, uint nv) -> pre_and_post_state {
 }
 
 
-fn expr_precond(&expr e) -> precond {
+fn expr_precond(@expr e) -> precond {
   ret (expr_pp(e)).precondition;
 }
 
-fn expr_postcond(&expr e) -> postcond {
+fn expr_postcond(@expr e) -> postcond {
   ret (expr_pp(e)).postcondition;
 }
 
-fn expr_prestate(&expr e) -> prestate {
+fn expr_prestate(@expr e) -> prestate {
   ret (expr_states(e)).prestate;
 }
 
-fn expr_poststate(&expr e) -> poststate {
+fn expr_poststate(@expr e) -> poststate {
   ret (expr_states(e)).poststate;
 }
 
@@ -737,7 +627,7 @@ fn seq_preconds(fn_info enclosing, vec[pre_and_post] pps) -> precond {
 
   if (sz >= 1u) {
     auto first   = pps.(0);
-    check (pps_len(first) == num_vars);
+    assert (pps_len(first) == num_vars);
     let precond rest = seq_preconds(enclosing,
                          slice[pre_and_post](pps, 1u, sz));
     difference(rest, first.postcondition);
@@ -797,7 +687,7 @@ fn intersect_postconds_go(&postcond first, &vec[postcond] rest) -> postcond {
 }
 
 fn intersect_postconds(&vec[postcond] pcs) -> postcond {
-  check (len[postcond](pcs) > 0u);
+  assert (len[postcond](pcs) > 0u);
 
   ret intersect_postconds_go(bitv.clone(pcs.(0)), pcs);
 }
@@ -826,7 +716,7 @@ fn find_pre_post_state_native_mod(&native_mod m) -> bool {
  
 fn find_pre_post_obj(&fn_info_map fm, _obj o) -> () {
     fn do_a_method(fn_info_map fm, &@method m) -> () {
-        check(fm.contains_key(m.node.id));
+        assert (fm.contains_key(m.node.id));
         find_pre_post_fn(fm, fm.get(m.node.id), m.node.meth);
     }
     auto f = bind do_a_method(fm,_);
@@ -836,7 +726,7 @@ fn find_pre_post_obj(&fn_info_map fm, _obj o) -> () {
 
 fn find_pre_post_state_obj(fn_info_map fm, _obj o) -> bool {
     fn do_a_method(fn_info_map fm, &@method m) -> bool {
-        check(fm.contains_key(m.node.id));
+        assert (fm.contains_key(m.node.id));
         ret find_pre_post_state_fn(fm, fm.get(m.node.id), m.node.meth);
     }
     auto f = bind do_a_method(fm,_);
@@ -849,10 +739,10 @@ fn find_pre_post_state_obj(fn_info_map fm, _obj o) -> bool {
 fn find_pre_post_item(fn_info_map fm, fn_info enclosing, &item i) -> () {
   alt (i.node) {
     case (ast.item_const(?id, ?t, ?e, ?di, ?a)) {
-        find_pre_post_expr(fm, enclosing, *e);
+        find_pre_post_expr(fm, enclosing, e);
     }
     case (ast.item_fn(?id, ?f, ?ps, ?di, ?a)) {
-      check (fm.contains_key(di));
+      assert (fm.contains_key(di));
       find_pre_post_fn(fm, fm.get(di), f);
     }
     case (ast.item_mod(?id, ?m, ?di)) {
@@ -883,14 +773,14 @@ fn find_pre_post_exprs(&fn_info_map fm, &fn_info enclosing,
 
     fn do_one(fn_info_map fm, fn_info enclosing,
               &@expr e) -> () {
-        find_pre_post_expr(fm, enclosing, *e);
+        find_pre_post_expr(fm, enclosing, e);
     }
     auto f = bind do_one(fm, enclosing, _);
 
     _vec.map[@expr, ()](f, args);
 
     fn get_pp(&@expr e) -> pre_and_post {
-        ret expr_pp(*e);
+        ret expr_pp(e);
     }
     auto g = get_pp;
     auto pps = _vec.map[@expr, pre_and_post](g, args);
@@ -904,31 +794,31 @@ fn find_pre_post_exprs(&fn_info_map fm, &fn_info enclosing,
 
 fn find_pre_post_loop(&fn_info_map fm, &fn_info enclosing, &@decl d,
      &@expr index, &block body, &ann a) -> () {
-    find_pre_post_expr(fm, enclosing, *index);
+    find_pre_post_expr(fm, enclosing, index);
     find_pre_post_block(fm, enclosing, body);
     auto loop_precond = declare_var(enclosing, decl_lhs(d),
-           seq_preconds(enclosing, vec(expr_pp(*index),
-                                                   block_pp(body))));
+           seq_preconds(enclosing, vec(expr_pp(index),
+                                       block_pp(body))));
     auto loop_postcond = intersect_postconds
-        (vec(expr_postcond(*index), block_postcond(body)));
+        (vec(expr_postcond(index), block_postcond(body)));
     set_pre_and_post(a, rec(precondition=loop_precond,
                             postcondition=loop_postcond));
 }
 
 /* Fills in annotations as a side effect. Does not rebuild the expr */
-fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
+fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, @expr e) -> () {
     auto num_local_vars = num_locals(enclosing);
 
     fn do_rand_(fn_info_map fm, fn_info enclosing, &@expr e) -> () {
-        find_pre_post_expr(fm, enclosing, *e);
+        find_pre_post_expr(fm, enclosing, e);
     }
     fn pp_one(&@expr e) -> pre_and_post {
-        ret expr_pp(*e);
+        ret expr_pp(e);
     }
     
         log("find_pre_post_expr (num_locals =" +
              uistr(num_local_vars) + "):");
-        log_expr(e);
+        log_expr(*e);
     
     alt (e.node) {
         case (expr_call(?operator, ?operands, ?a)) {
@@ -974,18 +864,18 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
             set_pre_and_post(a, empty_pre_post(num_local_vars));
         }
         case(expr_log(_, ?arg, ?a)) {
-            find_pre_post_expr(fm, enclosing, *arg);
-            set_pre_and_post(a, expr_pp(*arg));
+            find_pre_post_expr(fm, enclosing, arg);
+            set_pre_and_post(a, expr_pp(arg));
         }
         case (expr_chan(?arg, ?a)) {
-            find_pre_post_expr(fm, enclosing, *arg);
-            set_pre_and_post(a, expr_pp(*arg));
+            find_pre_post_expr(fm, enclosing, arg);
+            set_pre_and_post(a, expr_pp(arg));
         }
         case(expr_put(?opt, ?a)) {
             alt (opt) {
                 case (some[@expr](?arg)) {
-                    find_pre_post_expr(fm, enclosing, *arg);
-                    set_pre_and_post(a, expr_pp(*arg));
+                    find_pre_post_expr(fm, enclosing, arg);
+                    set_pre_and_post(a, expr_pp(arg));
                 }
                 case (none[@expr]) {
                     set_pre_and_post(a, empty_pre_post(num_local_vars));
@@ -1004,10 +894,10 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
         case (expr_assign(?lhs, ?rhs, ?a)) {
             alt (lhs.node) {
                 case (expr_path(?p, some[def](def_local(?d_id)), ?a_lhs)) {
-                    find_pre_post_expr(fm, enclosing, *rhs);
-                    set_pre_and_post(a, expr_pp(*rhs));
+                    find_pre_post_expr(fm, enclosing, rhs);
+                    set_pre_and_post(a, expr_pp(rhs));
                     log("gen:");
-                    log_expr(e);
+                    log_expr(*e);
                     gen(enclosing, a, d_id);
                 }
                 case (_) {
@@ -1020,10 +910,10 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
         case (expr_recv(?lhs, ?rhs, ?a)) {
             alt (lhs.node) {
                 case (expr_path(?p, some[def](def_local(?d_id)), ?a_lhs)) {
-                    find_pre_post_expr(fm, enclosing, *rhs);
-                    set_pre_and_post(a, expr_pp(*rhs));
+                    find_pre_post_expr(fm, enclosing, rhs);
+                    set_pre_and_post(a, expr_pp(rhs));
                     log("gen:");
-                    log_expr(e);
+                    log_expr(*e);
                     gen(enclosing, a, d_id);
                 }
                 case (_) {
@@ -1049,45 +939,45 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
                           postcondition=false_postcond(num_local_vars)));
                 }
                 case (some[@expr](?ret_val)) {
-                    find_pre_post_expr(fm, enclosing, *ret_val);
+                    find_pre_post_expr(fm, enclosing, ret_val);
                     let pre_and_post pp =
-                        rec(precondition=expr_precond(*ret_val),
+                        rec(precondition=expr_precond(ret_val),
                             postcondition=false_postcond(num_local_vars));
                     set_pre_and_post(a, pp);
                 }
             }
         }
         case (expr_be(?e, ?a)) {
-            find_pre_post_expr(fm, enclosing, *e);
-            set_pre_and_post(a, rec(precondition=expr_prestate(*e),
+            find_pre_post_expr(fm, enclosing, e);
+            set_pre_and_post(a, rec(precondition=expr_prestate(e),
                           postcondition=false_postcond(num_local_vars)));
         }
         case (expr_if(?antec, ?conseq, ?maybe_alt, ?a)) {
-            find_pre_post_expr(fm, enclosing, *antec);
+            find_pre_post_expr(fm, enclosing, antec);
             find_pre_post_block(fm, enclosing, conseq);
             alt (maybe_alt) {
                 case (none[@expr]) {
                     auto precond_res = seq_preconds(enclosing,
-                                                    vec(expr_pp(*antec),
+                                                    vec(expr_pp(antec),
                                                         block_pp(conseq)));
                     set_pre_and_post(a, rec(precondition=precond_res,
                                             postcondition=
-                                            expr_poststate(*antec)));
+                                            expr_poststate(antec)));
                 }
                 case (some[@expr](?altern)) {
-                    find_pre_post_expr(fm, enclosing, *altern);
+                    find_pre_post_expr(fm, enclosing, altern);
                     auto precond_true_case =
                         seq_preconds(enclosing,
-                                     vec(expr_pp(*antec), block_pp(conseq)));
+                                     vec(expr_pp(antec), block_pp(conseq)));
                     auto postcond_true_case = union_postconds
                         (num_local_vars,
-                         vec(expr_postcond(*antec), block_postcond(conseq)));
+                         vec(expr_postcond(antec), block_postcond(conseq)));
                     auto precond_false_case = seq_preconds
                         (enclosing,
-                         vec(expr_pp(*antec), expr_pp(*altern)));
+                         vec(expr_pp(antec), expr_pp(altern)));
                     auto postcond_false_case = union_postconds
                         (num_local_vars,
-                         vec(expr_postcond(*antec), expr_postcond(*altern)));
+                         vec(expr_postcond(antec), expr_postcond(altern)));
                     auto precond_res = union_postconds
                         (num_local_vars,
                          vec(precond_true_case, precond_false_case));
@@ -1107,31 +997,31 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
             find_pre_post_exprs(fm, enclosing, vec(l, r), a);
         }
         case (expr_unary(_,?operand,?a)) {
-            find_pre_post_expr(fm, enclosing, *operand);
-            set_pre_and_post(a, expr_pp(*operand));
+            find_pre_post_expr(fm, enclosing, operand);
+            set_pre_and_post(a, expr_pp(operand));
         }
         case (expr_cast(?operand, _, ?a)) {
-            find_pre_post_expr(fm, enclosing, *operand);
-            set_pre_and_post(a, expr_pp(*operand));
+            find_pre_post_expr(fm, enclosing, operand);
+            set_pre_and_post(a, expr_pp(operand));
         }
         case (expr_while(?test, ?body, ?a)) {
-            find_pre_post_expr(fm, enclosing, *test);
+            find_pre_post_expr(fm, enclosing, test);
             find_pre_post_block(fm, enclosing, body);
             set_pre_and_post(a,
               rec(precondition=
                   seq_preconds(enclosing,
-                                 vec(expr_pp(*test), 
+                                 vec(expr_pp(test), 
                                      block_pp(body))),
                   postcondition=
-                  intersect_postconds(vec(expr_postcond(*test),
+                  intersect_postconds(vec(expr_postcond(test),
                                           block_postcond(body)))));
         }
         case (expr_do_while(?body, ?test, ?a)) {
             find_pre_post_block(fm, enclosing, body);
-            find_pre_post_expr(fm, enclosing, *test);
+            find_pre_post_expr(fm, enclosing, test);
    
             auto loop_postcond = union_postconds(num_local_vars,
-                            vec(block_postcond(body), expr_postcond(*test)));
+                            vec(block_postcond(body), expr_postcond(test)));
             /* conservative approximination: if the body
                could break or cont, the test may never be executed */
             if (has_nonlocal_exits(body)) {
@@ -1141,7 +1031,7 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
             set_pre_and_post(a, 
                              rec(precondition=seq_preconds(enclosing,
                                              vec(block_pp(body),
-                                                 expr_pp(*test))),
+                                                 expr_pp(test))),
                    postcondition=loop_postcond));
         }
         case (expr_for(?d, ?index, ?body, ?a)) {
@@ -1154,7 +1044,7 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
             find_pre_post_exprs(fm, enclosing, vec(e, sub), a);
         }
         case (expr_alt(?e, ?alts, ?a)) {
-            find_pre_post_expr(fm, enclosing, *e);
+            find_pre_post_expr(fm, enclosing, e);
             fn do_an_alt(fn_info_map fm, fn_info enc, &arm an_alt)
                 -> pre_and_post {
                 find_pre_post_block(fm, enc, an_alt.block);
@@ -1170,7 +1060,7 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
                 intersect(pp.postcondition, next.postcondition);
                 ret pp;
             }
-            auto antec_pp = pp_clone(expr_pp(*e)); 
+            auto antec_pp = pp_clone(expr_pp(e)); 
             auto e_pp  = rec(precondition=empty_prestate(num_local_vars),
                              postcondition=false_postcond(num_local_vars));
             auto g = bind combine_pp(antec_pp, enclosing, _, _);
@@ -1181,8 +1071,8 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
             set_pre_and_post(a, alts_overall_pp);
         }
         case (expr_field(?operator, _, ?a)) {
-            find_pre_post_expr(fm, enclosing, *operator);
-            set_pre_and_post(a, expr_pp(*operator));
+            find_pre_post_expr(fm, enclosing, operator);
+            set_pre_and_post(a, expr_pp(operator));
         }
         case (expr_fail(?a)) {
             set_pre_and_post(a,
@@ -1191,10 +1081,14 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
                rec(precondition=empty_prestate(num_local_vars),
                    postcondition=false_postcond(num_local_vars)));
         }
-        case (expr_check_expr(?p, ?a)) {
+        case (expr_assert(?p, ?a)) {
+            find_pre_post_expr(fm, enclosing, p);
+            set_pre_and_post(a, expr_pp(p));
+        }
+        case (expr_check(?p, ?a)) {
             /* will need to change when we support arbitrary predicates... */
-            find_pre_post_expr(fm, enclosing, *p);
-            set_pre_and_post(a, expr_pp(*p));
+            find_pre_post_expr(fm, enclosing, p);
+            set_pre_and_post(a, expr_pp(p));
         }
         case(expr_bind(?operator, ?maybe_args, ?a)) {
             auto args = _vec.cat_options[@expr](maybe_args);
@@ -1211,21 +1105,21 @@ fn find_pre_post_expr(&fn_info_map fm, &fn_info enclosing, &expr e) -> () {
             set_pre_and_post(a, empty_pre_post(num_local_vars));
         }
         case (expr_ext(_, _, _, ?expanded, ?a)) {
-            find_pre_post_expr(fm, enclosing, *expanded);
-            set_pre_and_post(a, expr_pp(*expanded));
+            find_pre_post_expr(fm, enclosing, expanded);
+            set_pre_and_post(a, expr_pp(expanded));
         }
     }
 }
 
 fn gen(&fn_info enclosing, &ann a, def_id id) -> bool {
-  check(enclosing.contains_key(id));
+  assert (enclosing.contains_key(id));
   let uint i = (enclosing.get(id))._0;
   ret set_in_postcond(i, (ann_to_ts_ann_fail_more(a)).conditions);
 }
 
 fn declare_var(&fn_info enclosing, def_id id, prestate pre)
    -> prestate {
-    check(enclosing.contains_key(id));
+    assert (enclosing.contains_key(id));
     let uint i = (enclosing.get(id))._0;
     auto res = clone(pre);
     relax_prestate(i, res);
@@ -1233,7 +1127,7 @@ fn declare_var(&fn_info enclosing, def_id id, prestate pre)
 }
 
 fn gen_poststate(&fn_info enclosing, &ann a, def_id id) -> bool {
-  check(enclosing.contains_key(id));
+  assert (enclosing.contains_key(id));
   let uint i = (enclosing.get(id))._0;
 
   ret set_in_poststate(i, (ann_to_ts_ann_fail_more(a)).states);
@@ -1251,8 +1145,8 @@ fn find_pre_post_stmt(fn_info_map fm, &fn_info enclosing, &ast.stmt s)
             case(ast.decl_local(?alocal)) {
                 alt(alocal.init) {
                     case(some[ast.initializer](?an_init)) {
-                        find_pre_post_expr(fm, enclosing, *an_init.expr);
-                        auto rhs_pp = expr_pp(*an_init.expr);
+                        find_pre_post_expr(fm, enclosing, an_init.expr);
+                        auto rhs_pp = expr_pp(an_init.expr);
                         set_pre_and_post(alocal.ann, rhs_pp);
 
                         /* Inherit ann from initializer, and add var being
@@ -1281,8 +1175,8 @@ fn find_pre_post_stmt(fn_info_map fm, &fn_info enclosing, &ast.stmt s)
         }
     }
     case(stmt_expr(?e,?a)) {
-        find_pre_post_expr(fm, enclosing, *e);
-        set_pre_and_post(a, expr_pp(*e));
+        find_pre_post_expr(fm, enclosing, e);
+        set_pre_and_post(a, expr_pp(e));
     }    
   }
 }
@@ -1318,7 +1212,7 @@ fn find_pre_post_block(&fn_info_map fm, &fn_info enclosing, block b)
     
     _vec.map[@stmt, ()](do_one, b.node.stmts);
     fn do_inner_(fn_info_map fm, fn_info i, &@expr e) -> () {
-        find_pre_post_expr(fm, i, *e);
+        find_pre_post_expr(fm, i, e);
     }
     auto do_inner = bind do_inner_(fm, enclosing, _);
     option.map[@expr, ()](do_inner, b.node.expr);
@@ -1331,7 +1225,7 @@ fn find_pre_post_block(&fn_info_map fm, &fn_info enclosing, block b)
     auto f = get_pp_stmt;
     pps += _vec.map[@stmt, pre_and_post](f, b.node.stmts);
     fn get_pp_expr(&@expr e) -> pre_and_post {
-        ret expr_pp(*e);
+        ret expr_pp(e);
     }
     auto g = get_pp_expr;
     plus_option[pre_and_post](pps,
@@ -1363,7 +1257,7 @@ fn check_item_fn(&fn_info_map fm, &span sp, ident i, &ast._fn f,
     log("check_item_fn:");
     log_fn(f, i, ty_params);
 
-  check (fm.contains_key(id));
+  assert (fm.contains_key(id));
   find_pre_post_fn(fm, fm.get(id), f);  
 
   ret @respan(sp, ast.item_fn(i, f, ty_params, id, a));
@@ -1377,7 +1271,7 @@ fn find_pre_post_state_item(fn_info_map fm, fn_info enclosing, @item i)
               empty_prestate(num_locals(enclosing)), e);
     }
     case (ast.item_fn(?id, ?f, ?ps, ?di, ?a)) {
-      check (fm.contains_key(di));
+      assert (fm.contains_key(di));
       ret find_pre_post_state_fn(fm, fm.get(di), f);
     }
     case (ast.item_mod(?id, ?m, ?di)) {
@@ -1401,7 +1295,7 @@ fn find_pre_post_state_item(fn_info_map fm, fn_info enclosing, @item i)
 fn set_prestate_ann(@ann a, prestate pre) -> bool {
   alt (*a) {
     case (ann_type(_,_,?ts_a)) {
-      check (! is_none[@ts_ann](ts_a));
+      assert (! is_none[@ts_ann](ts_a));
       ret set_prestate(get[@ts_ann](ts_a), pre);
     }
     case (ann_none) {
@@ -1415,8 +1309,8 @@ fn set_prestate_ann(@ann a, prestate pre) -> bool {
 fn extend_prestate_ann(ann a, prestate pre) -> bool {
   alt (a) {
     case (ann_type(_,_,?ts_a)) {
-      check (! is_none[@ts_ann](ts_a));
-      ret extend_prestate((*get[@ts_ann](ts_a)).states.prestate, pre);
+      assert (! is_none[@ts_ann](ts_a));
+      ret extend_prestate((get[@ts_ann](ts_a)).states.prestate, pre);
     }
     case (ann_none) {
       log("set_prestate_ann: expected an ann_type here");
@@ -1428,8 +1322,8 @@ fn extend_prestate_ann(ann a, prestate pre) -> bool {
 fn set_poststate_ann(ann a, poststate post) -> bool {
   alt (a) {
     case (ann_type(_,_,?ts_a)) {
-      check (! is_none[@ts_ann](ts_a));
-      ret set_poststate(*get[@ts_ann](ts_a), post);
+      assert (! is_none[@ts_ann](ts_a));
+      ret set_poststate(get[@ts_ann](ts_a), post);
     }
     case (ann_none) {
       log("set_poststate_ann: expected an ann_type here");
@@ -1441,7 +1335,7 @@ fn set_poststate_ann(ann a, poststate post) -> bool {
 fn extend_poststate_ann(ann a, poststate post) -> bool {
   alt (a) {
     case (ann_type(_,_,?ts_a)) {
-      check (! is_none[@ts_ann](ts_a));
+      assert (! is_none[@ts_ann](ts_a));
       ret extend_poststate((*get[@ts_ann](ts_a)).states.poststate, post);
     }
     case (ann_none) {
@@ -1454,7 +1348,7 @@ fn extend_poststate_ann(ann a, poststate post) -> bool {
 fn set_pre_and_post(&ann a, pre_and_post pp) -> () {
     alt (a) {
         case (ann_type(_,_,?ts_a)) {
-            check (! is_none[@ts_ann](ts_a));
+            assert (! is_none[@ts_ann](ts_a));
             auto t = *get[@ts_ann](ts_a);
             /*  log("set_pre_and_post, old =");
             log_pp(t.conditions);
@@ -1478,7 +1372,7 @@ fn seq_states(&fn_info_map fm, &fn_info enclosing,
 
   for (@expr e in exprs) {
     changed = find_pre_post_state_expr(fm, enclosing, post, e) || changed;
-    post = expr_poststate(*e);
+    post = expr_poststate(e);
   }
 
   ret tup(changed, post);
@@ -1513,8 +1407,8 @@ fn find_pre_post_state_loop(fn_info_map fm, fn_info enclosing,
     /* in general, would need the intersection of
        (poststate of index, poststate of body) */
     changed = find_pre_post_state_block(fm, enclosing,
-                expr_poststate(*index), body) || changed;
-    auto res_p = intersect_postconds(vec(expr_poststate(*index),
+                expr_poststate(index), body) || changed;
+    auto res_p = intersect_postconds(vec(expr_poststate(index),
                                          block_poststate(body)));
   
     changed = extend_poststate_ann(a, res_p) || changed;
@@ -1522,7 +1416,7 @@ fn find_pre_post_state_loop(fn_info_map fm, fn_info enclosing,
 }
 
 fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
-                            &prestate pres, &@expr e) -> bool {
+                            &prestate pres, @expr e) -> bool {
   auto changed = false;
   auto num_local_vars = num_locals(enclosing);
 
@@ -1540,20 +1434,20 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         || changed;
       /* rands go left-to-right */
       ret(find_pre_post_state_exprs(fm, enclosing,
-                                    expr_poststate(*operator), a, operands)
+                                    expr_poststate(operator), a, operands)
           || changed);
     }
     case (expr_spawn(_, _, ?operator, ?operands, ?a)) {
         changed = find_pre_post_state_expr(fm, enclosing, pres, operator);
         ret(find_pre_post_state_exprs(fm, enclosing,
-                 expr_poststate(*operator), a, operands)
+                 expr_poststate(operator), a, operands)
           || changed);
     }
     case (expr_bind(?operator, ?maybe_args, ?a)) {
         changed = find_pre_post_state_expr(fm, enclosing, pres, operator)
             || changed;
         ret (find_pre_post_state_exprs(fm, enclosing,
-          expr_poststate(*operator), a, cat_options[@expr](maybe_args))
+          expr_poststate(operator), a, cat_options[@expr](maybe_args))
             || changed);
     }
     case (expr_path(_,_,?a)) {
@@ -1563,19 +1457,19 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         /* factor out the "one exp" pattern */
         changed = find_pre_post_state_expr(fm, enclosing, pres, e);
         changed = extend_prestate_ann(a, pres) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*e)) || changed;
+        changed = extend_poststate_ann(a, expr_poststate(e)) || changed;
         ret changed;
     }
     case (expr_chan(?e, ?a)) {
         changed = find_pre_post_state_expr(fm, enclosing, pres, e);
         changed = extend_prestate_ann(a, pres) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*e)) || changed;
+        changed = extend_poststate_ann(a, expr_poststate(e)) || changed;
         ret changed;
     }
     case (expr_ext(_, _, _, ?expanded, ?a)) {
         changed = find_pre_post_state_expr(fm, enclosing, pres, expanded);
         changed = extend_prestate_ann(a, pres) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*expanded))
+        changed = extend_poststate_ann(a, expr_poststate(expanded))
            || changed;
         ret changed;
     }
@@ -1584,7 +1478,7 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
             case (some[@expr](?arg)) {
                 changed = find_pre_post_state_expr(fm, enclosing, pres, arg);
                 changed = extend_prestate_ann(a, pres) || changed;
-                changed = extend_poststate_ann(a, expr_poststate(*arg))
+                changed = extend_poststate_ann(a, expr_poststate(arg))
                     || changed;
                 ret changed;
             }
@@ -1611,7 +1505,7 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
             case (some[@expr](?base)) {
                 changed = find_pre_post_state_expr(fm, enclosing, pres, base)
                     || changed;
-                changed = extend_poststate_ann(a, expr_poststate(*base))
+                changed = extend_poststate_ann(a, expr_poststate(base))
                     || changed;
             }
         }
@@ -1626,7 +1520,7 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
                 changed = pure_exp(a_lhs, pres) || changed;
                 changed = find_pre_post_state_expr(fm, enclosing, pres, rhs)
                     || changed;
-                changed = extend_poststate_ann(a, expr_poststate(*rhs))
+                changed = extend_poststate_ann(a, expr_poststate(rhs))
                     || changed;
                 changed = gen_poststate(enclosing, a, d_id) || changed;
             }
@@ -1635,8 +1529,8 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
                 changed = find_pre_post_state_expr(fm, enclosing, pres, lhs)
                     || changed;
                 changed = find_pre_post_state_expr(fm, enclosing,
-                     expr_poststate(*lhs), rhs) || changed;
-                changed = extend_poststate_ann(a, expr_poststate(*rhs))
+                     expr_poststate(lhs), rhs) || changed;
+                changed = extend_poststate_ann(a, expr_poststate(rhs))
                     || changed;
             }
         }
@@ -1651,7 +1545,7 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
                 changed = pure_exp(a_lhs, pres) || changed;
                 changed = find_pre_post_state_expr(fm, enclosing, pres, rhs)
                     || changed;
-                changed = extend_poststate_ann(a, expr_poststate(*rhs))
+                changed = extend_poststate_ann(a, expr_poststate(rhs))
                     || changed;
                 changed = gen_poststate(enclosing, a, d_id) || changed;
             }
@@ -1660,8 +1554,8 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
                 changed = find_pre_post_state_expr(fm, enclosing, pres, lhs)
                     || changed;
                 changed = find_pre_post_state_expr(fm, enclosing,
-                     expr_poststate(*lhs), rhs) || changed;
-                changed = extend_poststate_ann(a, expr_poststate(*rhs))
+                     expr_poststate(lhs), rhs) || changed;
+                changed = extend_poststate_ann(a, expr_poststate(rhs))
                     || changed;
             }
         }
@@ -1691,17 +1585,17 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         changed = find_pre_post_state_expr(fm, enclosing, pres, antec)
             || changed;
         changed = find_pre_post_state_block(fm, enclosing,
-          expr_poststate(*antec), conseq) || changed;
+          expr_poststate(antec), conseq) || changed;
         alt (maybe_alt) {
             case (none[@expr]) {
-                changed = extend_poststate_ann(a, expr_poststate(*antec))
+                changed = extend_poststate_ann(a, expr_poststate(antec))
                     || changed;
             }
             case (some[@expr](?altern)) {
                 changed = find_pre_post_state_expr(fm, enclosing,
-                   expr_poststate(*antec), altern) || changed;
+                   expr_poststate(antec), altern) || changed;
                 auto poststate_res = intersect_postconds
-                    (vec(block_poststate(conseq), expr_poststate(*altern)));
+                    (vec(block_poststate(conseq), expr_poststate(altern)));
                 changed = extend_poststate_ann(a, poststate_res) || changed;
             }
         }
@@ -1710,7 +1604,7 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         log("new prestate:");
         log_bitv(enclosing, pres);
         log("new poststate:");
-        log_bitv(enclosing, expr_poststate(*e));
+        log_bitv(enclosing, expr_poststate(e));
 
         ret changed;
     }
@@ -1720,8 +1614,8 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         changed = find_pre_post_state_expr(fm, enclosing, pres, l)
                     || changed;
         changed = find_pre_post_state_expr(fm,
-                    enclosing, expr_poststate(*l), r) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*r)) || changed;
+                    enclosing, expr_poststate(l), r) || changed;
+        changed = extend_poststate_ann(a, expr_poststate(r)) || changed;
         ret changed;
     }
     case (expr_send(?l, ?r, ?a)) {
@@ -1729,8 +1623,8 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         changed = find_pre_post_state_expr(fm, enclosing, pres, l)
                     || changed;
         changed = find_pre_post_state_expr(fm,
-                    enclosing, expr_poststate(*l), r) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*r)) || changed;
+                    enclosing, expr_poststate(l), r) || changed;
+        changed = extend_poststate_ann(a, expr_poststate(r)) || changed;
         ret changed;
     }
     case (expr_assign_op(?op, ?lhs, ?rhs, ?a)) {
@@ -1739,8 +1633,8 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         changed = find_pre_post_state_expr(fm, enclosing, pres, lhs)
                     || changed;
         changed = find_pre_post_state_expr(fm,
-                    enclosing, expr_poststate(*lhs), rhs) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*rhs)) || changed;
+                    enclosing, expr_poststate(lhs), rhs) || changed;
+        changed = extend_poststate_ann(a, expr_poststate(rhs)) || changed;
         ret changed;
     }
     case (expr_while(?test, ?body, ?a)) {
@@ -1756,9 +1650,9 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         changed = find_pre_post_state_expr(fm, enclosing, pres, test)
             || changed;
         changed = find_pre_post_state_block(fm, 
-                   enclosing, expr_poststate(*test), body) || changed; 
+                   enclosing, expr_poststate(test), body) || changed; 
         changed = extend_poststate_ann(a,
-                    intersect_postconds(vec(expr_poststate(*test),
+                    intersect_postconds(vec(expr_poststate(test),
                                         block_poststate(body)))) || changed;
         ret changed;
     }
@@ -1777,7 +1671,7 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
             changed = set_poststate_ann(a, pres) || changed;
         }
         else {
-            changed = extend_poststate_ann(a, expr_poststate(*test))
+            changed = extend_poststate_ann(a, expr_poststate(test))
               || changed;
         }
 
@@ -1793,14 +1687,14 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         changed = extend_prestate_ann(a, pres) || changed; 
         changed = find_pre_post_state_expr(fm, enclosing, pres, e) || changed;
         changed = find_pre_post_state_expr(fm, enclosing,
-                     expr_poststate(*e), sub) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*sub));
+                     expr_poststate(e), sub) || changed;
+        changed = extend_poststate_ann(a, expr_poststate(sub));
         ret changed;
     }
     case (expr_alt(?e, ?alts, ?a)) {
         changed = extend_prestate_ann(a, pres) || changed; 
         changed = find_pre_post_state_expr(fm, enclosing, pres, e) || changed;
-        auto e_post = expr_poststate(*e);
+        auto e_post = expr_poststate(e);
         auto a_post;
         if (_vec.len[arm](alts) > 0u) {
             a_post = false_postcond(num_local_vars);
@@ -1821,14 +1715,14 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
     case (expr_field(?e,_,?a)) {
         changed = find_pre_post_state_expr(fm, enclosing, pres, e);
         changed = extend_prestate_ann(a, pres) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*e)) || changed;
+        changed = extend_poststate_ann(a, expr_poststate(e)) || changed;
         ret changed;
     }
     case (expr_unary(_,?operand,?a)) {
         changed = find_pre_post_state_expr(fm, enclosing, pres, operand)
           || changed;
         changed = extend_prestate_ann(a, pres) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*operand))
+        changed = extend_poststate_ann(a, expr_poststate(operand))
           || changed;
         ret changed;
     }
@@ -1836,7 +1730,7 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
            changed = find_pre_post_state_expr(fm, enclosing, pres, operand)
           || changed;
         changed = extend_prestate_ann(a, pres) || changed;
-        changed = extend_poststate_ann(a, expr_poststate(*operand))
+        changed = extend_poststate_ann(a, expr_poststate(operand))
           || changed;
         ret changed;
     }
@@ -1845,14 +1739,15 @@ fn find_pre_post_state_expr(&fn_info_map fm, &fn_info enclosing,
         /* if execution continues after fail, then everything is true! woo! */
         changed = set_poststate_ann(a, false_postcond(num_local_vars))
           || changed;
-        /*        log_err("fail: poststate = ");
-                  log_bitv(enclosing, expr_poststate(*e)); */
         ret changed;
     }
-    case (expr_check_expr(?p, ?a)) {
+    case (expr_assert(?p, ?a)) {
+        ret pure_exp(a, pres);
+    }
+    case (expr_check(?p, ?a)) {
         changed = extend_prestate_ann(a, pres) || changed;
         changed = find_pre_post_state_expr(fm, enclosing, pres, p) || changed;
-        /* p is pure, so the poststate must be the same as the prestate */
+        /* FIXME: update the postcondition to reflect that p holds */
         changed = extend_poststate_ann(a, pres) || changed;
         ret changed;
     }
@@ -1875,7 +1770,7 @@ fn find_pre_post_state_stmt(&fn_info_map fm, &fn_info enclosing,
                             &prestate pres, @stmt s) -> bool {
   auto changed = false;
   auto stmt_ann_ = stmt_to_ann(*s);
-  check (!is_none[@ts_ann](stmt_ann_));
+  assert (!is_none[@ts_ann](stmt_ann_));
   auto stmt_ann = *(get[@ts_ann](stmt_ann_));
               log("*At beginning: stmt = ");
               log_stmt(*s);
@@ -1897,7 +1792,7 @@ fn find_pre_post_state_stmt(&fn_info_map fm, &fn_info enclosing,
                 changed = find_pre_post_state_expr
                     (fm, enclosing, pres, an_init.expr) || changed;
                 changed = extend_poststate(stmt_ann.states.poststate,
-                                           expr_poststate(*an_init.expr))
+                                           expr_poststate(an_init.expr))
                     || changed;
                 changed = gen_poststate(enclosing, a, alocal.id) || changed;
               log("Summary: stmt = ");
@@ -1932,10 +1827,10 @@ fn find_pre_post_state_stmt(&fn_info_map fm, &fn_info enclosing,
     }
     case (stmt_expr(?e, _)) {
       changed = find_pre_post_state_expr(fm, enclosing, pres, e) || changed;
-      changed = extend_prestate(stmt_ann.states.prestate, expr_prestate(*e))
+      changed = extend_prestate(stmt_ann.states.prestate, expr_prestate(e))
           || changed;
       changed = extend_poststate(stmt_ann.states.poststate,
-                                 expr_poststate(*e)) || changed;
+                                 expr_poststate(e)) || changed;
       /*
                     log("Summary: stmt = ");
               log_stmt(*s);
@@ -1980,7 +1875,7 @@ fn find_pre_post_state_block(&fn_info_map fm, &fn_info enclosing,
     case (none[@expr]) {}
     case (some[@expr](?e)) {
       changed = find_pre_post_state_expr(fm, enclosing, pres, e) || changed;
-      post = expr_poststate(*e);
+      post = expr_poststate(e);
     }
   }
 
@@ -2038,13 +1933,13 @@ fn fixed_point_states(fn_info_map fm, fn_info f_info,
   }
 }
 
-fn check_states_expr(fn_info enclosing, &expr e) -> () {
+fn check_states_expr(fn_info enclosing, @expr e) -> () {
   let precond prec    = expr_precond(e);
   let prestate pres   = expr_prestate(e);
 
   if (!implies(pres, prec)) {
       log_err("check_states_expr: Unsatisfied precondition constraint for ");
-      log_expr_err(e);
+      log_expr_err(*e);
       log_err("Precondition: ");
       log_bitv_err(enclosing, prec);
       log_err("Prestate: ");
@@ -2093,7 +1988,7 @@ fn check_states_against_conditions(fn_info enclosing, &ast._fn f) -> () {
  
   _vec.map[@stmt, ()](do_one, f.body.node.stmts);
   fn do_inner_(fn_info i, &@expr e) -> () {
-    check_states_expr(i, *e);
+    check_states_expr(i, e);
   }
   auto do_inner = bind do_inner_(enclosing, _);
   option.map[@expr, ()](do_inner, f.body.node.expr);
@@ -2116,7 +2011,7 @@ fn check_item_fn_state(&fn_info_map f_info_map, &span sp, ident i,
                        ann a) -> @item {
 
   /* Look up the var-to-bit-num map for this function */
-  check(f_info_map.contains_key(id));
+  assert (f_info_map.contains_key(id));
   auto f_info = f_info_map.get(id);
 
   check_fn_states(f_info_map, f_info, f);
@@ -2126,7 +2021,7 @@ fn check_item_fn_state(&fn_info_map f_info_map, &span sp, ident i,
 }
 
 fn check_method_states(&fn_info_map f_info_map, @method m) -> () {
-    check (f_info_map.contains_key(m.node.id));
+    assert (f_info_map.contains_key(m.node.id));
     auto f_info = f_info_map.get(m.node.id);
     check_fn_states(f_info_map, f_info, m.node.meth);
 }
@@ -2193,7 +2088,7 @@ fn init_block(&fn_info fi, &span sp, &block_ b) -> block {
 fn item_fn_anns(&fn_info_map fm, &span sp, ident i, &ast._fn f,
                 vec[ast.ty_param] ty_params, def_id id, ann a) -> @item {
 
-    check(fm.contains_key(id));
+    assert (fm.contains_key(id));
     auto f_info = fm.get(id);
 
     log(i + " has " + uistr(num_locals(f_info)) + " local vars");
@@ -2413,8 +2308,11 @@ fn annotate_expr(&fn_info_map fm, &@expr e) -> @expr {
         case (expr_log(?n, ?e, ?a)) {
             e1 = expr_log(n, annotate_expr(fm, e), a);
         }
-        case (expr_check_expr(?e, ?a)) {
-            e1 = expr_check_expr(annotate_expr(fm, e), a);
+        case (expr_assert(?e, ?a)) {
+            e1 = expr_assert(annotate_expr(fm, e), a);
+        }
+        case (expr_check(?e, ?a)) {
+            e1 = expr_check(annotate_expr(fm, e), a);
         }
         case (expr_port(_)) { /* no change */ }
         case (expr_chan(?e, ?a)) {

src/comp/middle/walk.rs

@@ -392,7 +392,10 @@ fn walk_expr(&ast_visitor v, @ast.expr e) {
         case (ast.expr_log(_,?x, _)) {
             walk_expr(v, x);
         }
-        case (ast.expr_check_expr(?x, _)) {
+        case (ast.expr_check(?x, _)) {
+            walk_expr(v, x);
+        }
+        case (ast.expr_assert(?x, _)) {
             walk_expr(v, x);
         }
         case (ast.expr_port(_)) { }

src/comp/pretty/pprust.rs

@@ -661,12 +661,18 @@ fn print_expr(ps s, &@ast.expr expr) {
             }
             print_expr(s, expr);
         }
-        case (ast.expr_check_expr(?expr,_)) {
+        case (ast.expr_check(?expr,_)) {
             wrd1(s, "check");
             popen_h(s);
             print_expr(s, expr);
             pclose(s);
         }
+        case (ast.expr_assert(?expr,_)) {
+            wrd1(s, "assert");
+            popen_h(s);
+            print_expr(s, expr);
+            pclose(s);
+        }
         case (ast.expr_ext(?path, ?args, ?body, _, _)) {
             wrd(s.s, "#");
             print_path(s, path);

src/comp/util/typestate_ann.rs

@@ -85,7 +85,7 @@ fn intersect(&precond p1, &precond p2) -> bool {
 
 fn pps_len(&pre_and_post p) -> uint {
   // gratuitous check
-  check (p.precondition.nbits == p.postcondition.nbits);
+  assert (p.precondition.nbits == p.postcondition.nbits);
   ret p.precondition.nbits;
 }
 
@@ -129,7 +129,7 @@ fn set_prestate(@ts_ann a, &prestate p) -> bool {
 
 // Sets all the bits in a's postcondition to equal the
 // corresponding bit in p's postcondition.
-fn set_poststate(&ts_ann a, &poststate p) -> bool {
+fn set_poststate(@ts_ann a, &poststate p) -> bool {
   ret bitv.copy(a.states.poststate, p);
 }
 

src/lib/Term.rs

@@ -35,7 +35,7 @@ fn color_supported() -> bool {
 }
 
 fn set_color(io.buf_writer writer, u8 first_char, u8 color) {
-    check (color < 16u8);
+    assert (color < 16u8);
 
     esc(writer);
     if (color >= 8u8) {

src/lib/_int.rs

@@ -27,7 +27,7 @@ iter range(int lo, int hi) -> int {
 
 fn to_str(int n, uint radix) -> str
 {
-    check (0u < radix && radix <= 16u);
+    assert (0u < radix && radix <= 16u);
     if (n < 0) {
         ret "-" + _uint.to_str((-n) as uint, radix);
     } else {

src/lib/_str.rs

@@ -218,14 +218,14 @@ fn utf8_char_width(u8 b) -> uint {
 fn char_range_at(str s, uint i) -> tup(char, uint) {
     auto b0 = s.(i);
     auto w = utf8_char_width(b0);
-    check(w != 0u);
+    assert (w != 0u);
     if (w == 1u) {ret tup(b0 as char, i + 1u);}
     auto val = 0u;
     auto end = i + w;
     i += 1u;
     while (i < end) {
         auto byte = s.(i);
-        check(byte & 0xc0_u8 == tag_cont_u8);
+        assert (byte & 0xc0_u8 == tag_cont_u8);
         val <<= 6u;
         val += (byte & 0x3f_u8) as uint;
         i += 1u;
@@ -247,11 +247,11 @@ fn char_len(str s) -> uint {
     auto total = byte_len(s);
     while (i < total) {
         auto chsize = utf8_char_width(s.(i));
-        check(chsize > 0u);
+        assert (chsize > 0u);
         len += 1u;
         i += chsize;
     }
-    check(i == total);
+    assert (i == total);
     ret len;
 }
 
@@ -274,7 +274,7 @@ fn push_char(&mutable str s, char ch) {
 fn pop_char(&mutable str s) -> char {
     auto end = byte_len(s);
     while (end > 0u && s.(end - 1u) & 0xc0_u8 == tag_cont_u8) {end -= 1u;}
-    check(end > 0u);
+    assert (end > 0u);
     auto ch = char_at(s, end - 1u);
     s = substr(s, 0u, end - 1u);
     ret ch;
@@ -404,7 +404,7 @@ fn slice(str s, uint begin, uint end) -> str {
 
 fn shift_byte(&mutable str s) -> u8 {
     auto len = byte_len(s);
-    check(len > 0u);
+    assert (len > 0u);
     auto b = s.(0);
     s = substr(s, 1u, len - 1u);
     ret b;
@@ -412,7 +412,7 @@ fn shift_byte(&mutable str s) -> u8 {
 
 fn pop_byte(&mutable str s) -> u8 {
     auto len = byte_len(s);
-    check(len > 0u);
+    assert (len > 0u);
     auto b = s.(len - 1u);
     s = substr(s, 0u, len - 1u);
     ret b;

src/lib/_uint.rs

@@ -56,7 +56,7 @@ fn to_str(uint num, uint radix) -> str
 {
     auto n = num;
 
-    check (0u < radix && radix <= 16u);
+    assert (0u < radix && radix <= 16u);
     fn digit(uint n) -> char {
         alt (n) {
             case (0u) { ret '0'; }

src/lib/_vec.rs

@@ -131,7 +131,7 @@ fn len_set[T](array[T] v, uint n) {
 }
 
 fn buf_off[T](array[T] v, uint offset) -> vbuf {
-    check (offset < len[T](v));
+     assert (offset < len[T](v));
     ret rustrt.vec_buf[T](v, offset);
 }
 
@@ -149,9 +149,10 @@ fn last[T](array[T] v) -> option.t[T] {
 }
 
 // Returns elements from [start..end) from v.
+
 fn slice[T](array[T] v, uint start, uint end) -> vec[T] {
-    check (start <= end);
-    check (end <= len[T](v));
+    assert (start <= end);
+    assert (end <= len[T](v));
     auto result = alloc[T](end - start);
     let uint i = start;
     while (i < end) {
@@ -163,7 +164,7 @@ fn slice[T](array[T] v, uint start, uint end) -> vec[T] {
 
 fn shift[T](&mutable array[T] v) -> T {
     auto ln = len[T](v);
-    check(ln > 0u);
+    assert (ln > 0u);
     auto e = v.(0);
     v = slice[T](v, 1u, ln);
     ret e;
@@ -171,7 +172,7 @@ fn shift[T](&mutable array[T] v) -> T {
 
 fn pop[T](&mutable array[T] v) -> T {
     auto ln = len[T](v);
-    check(ln > 0u);
+    assert (ln > 0u);
     ln -= 1u;
     auto e = v.(ln);
     v = slice[T](v, 0u, ln);

src/lib/bitv.rs

@@ -28,8 +28,8 @@ fn create(uint nbits, bool init) -> t {
 fn process(&fn(uint, uint) -> uint op, &t v0, &t v1) -> bool {
     auto len = _vec.len[mutable uint](v1.storage);
 
-    check (_vec.len[mutable uint](v0.storage) == len);
-    check (v0.nbits == v1.nbits);
+    assert (_vec.len[mutable uint](v0.storage) == len);
+    assert (v0.nbits == v1.nbits);
 
     auto changed = false;
 
@@ -84,7 +84,7 @@ fn clone(t v) -> t {
 }
 
 fn get(&t v, uint i) -> bool {
-    check (i < v.nbits);
+    assert (i < v.nbits);
 
     auto bits = uint_bits();
 
@@ -129,7 +129,7 @@ fn difference(&t v0, &t v1) -> bool {
 }
 
 fn set(&t v, uint i, bool x) {
-    check (i < v.nbits);
+    assert (i < v.nbits);
 
     auto bits = uint_bits();
 
@@ -196,7 +196,7 @@ fn to_str(&t v) -> str {
 
 // FIXME: can we just use structural equality on to_vec?
 fn eq_vec(&t v0, &vec[uint] v1) -> bool {
-    check (v0.nbits == _vec.len[uint](v1));
+    assert (v0.nbits == _vec.len[uint](v1));
     auto len = v0.nbits;
     auto i = 0u;
     while (i < len) {

src/lib/deque.rs

@@ -28,7 +28,7 @@ fn create[T]() -> t[T] {
      * elsewhere.
      */
     fn grow[T](uint nelts, uint lo, vec[cell[T]] elts) -> vec[cell[T]] {
-        check (nelts == _vec.len[cell[T]](elts));
+        assert (nelts == _vec.len[cell[T]](elts));
 
         fn fill[T](uint i, uint nelts, uint lo,
                    vec[cell[T]] old) -> cell[T] {

src/lib/ebml.rs

@@ -99,7 +99,7 @@ fn doc_data(doc d) -> vec[u8] {
 
 fn be_uint_from_bytes(vec[u8] data, uint start, uint size) -> uint {
     auto sz = size;
-    check (sz <= 4u);
+    assert (sz <= 4u);
     auto val = 0u;
     auto pos = start;
     while (sz > 0u) {

src/lib/fs.rs

@@ -10,7 +10,7 @@ type path = str;
 
 fn dirname(path p) -> path {
     auto sep = path_sep();
-    check (_str.byte_len(sep) == 1u);
+    assert (_str.byte_len(sep) == 1u);
     let int i = _str.rindex(p, sep.(0));
     if (i == -1) {
         ret p;

src/lib/io.rs

@@ -72,7 +72,7 @@ state obj FILE_buf_reader(os.libc.FILE f, bool must_close) {
         ret os.libc.feof(f) != 0;
     }
     fn seek(int offset, seek_style whence) {
-        check (os.libc.fseek(f, offset, convert_whence(whence)) == 0);
+        assert (os.libc.fseek(f, offset, convert_whence(whence)) == 0);
     }
     fn tell() -> uint {
         ret os.libc.ftell(f) as uint;
@@ -101,14 +101,14 @@ state obj new_reader(buf_reader rdr) {
         if (c0 == -1) {ret -1 as char;} // FIXME will this stay valid?
         auto b0 = c0 as u8;
         auto w = _str.utf8_char_width(b0);
-        check(w > 0u);
+        assert (w > 0u);
         if (w == 1u) {ret b0 as char;}
         auto val = 0u;
         while (w > 1u) {
             w -= 1u;
             auto next = rdr.read_byte();
-            check(next > -1);
-            check(next & 0xc0 == 0x80);
+            assert (next > -1);
+            assert (next & 0xc0 == 0x80);
             val <<= 6u;
             val += (next & 0x3f) as uint;
         }
@@ -279,7 +279,7 @@ state obj FILE_writer(os.libc.FILE f, bool must_close) {
     }
 
     fn seek(int offset, seek_style whence) {
-        check(os.libc.fseek(f, offset, convert_whence(whence)) == 0);
+        assert (os.libc.fseek(f, offset, convert_whence(whence)) == 0);
     }
 
     fn tell() -> uint {

src/lib/linux_os.rs

@@ -66,7 +66,7 @@ fn dylib_filename(str base) -> str {
 
 fn pipe() -> tup(int, int) {
     let vec[mutable int] fds = vec(mutable 0, 0);
-    check(os.libc.pipe(_vec.buf[mutable int](fds)) == 0);
+    assert (os.libc.pipe(_vec.buf[mutable int](fds)) == 0);
     ret tup(fds.(0), fds.(1));
 }
 
@@ -76,7 +76,7 @@ fn fd_FILE(int fd) -> libc.FILE {
 
 fn waitpid(int pid) -> int {
     let vec[mutable int] status = vec(mutable 0);
-    check(os.libc.waitpid(pid, _vec.buf[mutable int](status), 0) != -1);
+    assert (os.libc.waitpid(pid, _vec.buf[mutable int](status), 0) != -1);
     ret status.(0);
 }
 

src/lib/macos_os.rs

@@ -63,7 +63,7 @@ fn dylib_filename(str base) -> str {
 
 fn pipe() -> tup(int, int) {
     let vec[mutable int] fds = vec(mutable 0, 0);
-    check(os.libc.pipe(_vec.buf[mutable int](fds)) == 0);
+    assert (os.libc.pipe(_vec.buf[mutable int](fds)) == 0);
     ret tup(fds.(0), fds.(1));
 }
 
@@ -73,7 +73,7 @@ fn fd_FILE(int fd) -> libc.FILE {
 
 fn waitpid(int pid) -> int {
     let vec[mutable int] status = vec(mutable 0);
-    check(os.libc.waitpid(pid, _vec.buf[mutable int](status), 0) != -1);
+    assert (os.libc.waitpid(pid, _vec.buf[mutable int](status), 0) != -1);
     ret status.(0);
 }
 

src/lib/posix_fs.rs

@@ -5,7 +5,7 @@ native "rust" mod rustrt {
 fn list_dir(str path) -> vec[str] {
   // TODO ensure this is always closed
   auto dir = os.libc.opendir(_str.buf(path));
-  check (dir as uint != 0u);
+  assert (dir as uint != 0u);
   let vec[str] result = vec();
   while (true) {
     auto ent = os.libc.readdir(dir);

src/lib/sha1.rs

@@ -43,7 +43,7 @@ fn mk_sha1() -> sha1 {
 
     fn add_input(&sha1state st, &vec[u8] msg) {
         // FIXME: Should be typestate precondition
-        check (!st.computed);
+        assert (!st.computed);
 
         for (u8 element in msg) {
             st.msg_block.(st.msg_block_idx) = element;
@@ -67,7 +67,7 @@ fn mk_sha1() -> sha1 {
     fn process_msg_block(&sha1state st) {
 
         // FIXME: Make precondition
-        check (_vec.len[mutable u32](st.h) == digest_buf_len);
+        assert (_vec.len[mutable u32](st.h) == digest_buf_len);
 
         // Constants
         auto k = vec(0x5A827999u32,
@@ -192,7 +192,7 @@ fn mk_sha1() -> sha1 {
      */
     fn pad_msg(&sha1state st) {
         // FIXME: Should be a precondition
-        check (_vec.len[mutable u8](st.msg_block) == msg_block_len);
+        assert (_vec.len[mutable u8](st.msg_block) == msg_block_len);
 
         /*
          * Check to see if the current message block is too small to hold
@@ -236,7 +236,7 @@ fn mk_sha1() -> sha1 {
 
         fn reset() {
             // FIXME: Should be typestate precondition
-            check (_vec.len[mutable u32](st.h) == digest_buf_len);
+            assert (_vec.len[mutable u32](st.h) == digest_buf_len);
 
             st.len_low = 0u32;
             st.len_high = 0u32;

src/lib/win32_os.rs

@@ -53,7 +53,7 @@ fn dylib_filename(str base) -> str {
 
 fn pipe() -> tup(int, int) {
     let vec[mutable int] fds = vec(mutable 0, 0);
-    check(os.libc._pipe(_vec.buf[mutable int](fds), 1024u,
+    assert (os.libc._pipe(_vec.buf[mutable int](fds), 1024u,
                         libc_constants.O_BINARY()) == 0);
     ret tup(fds.(0), fds.(1));
 }

src/test/run-fail/fail.rs

@@ -2,5 +2,5 @@
 // error-pattern:1 == 2
 
 fn main() {
-   check (1 == 2);
+   assert (1 == 2);
 }

src/test/run-fail/linked-failure.rs

@@ -4,7 +4,7 @@
 // error-pattern:1 == 2
 
 fn child() {
-  check (1 == 2);
+  assert (1 == 2);
 }
 
 fn main() {

src/test/run-fail/str-overrun.rs

@@ -6,12 +6,12 @@
 fn main() {
   let str s = "hello";
   let int x = 0;
-  check (s.(x) == (0x68 as u8));
+  assert (s.(x) == (0x68 as u8));
 
   // NB: at the moment a string always has a trailing NULL,
   // so the largest index value on the string above is 5, not
   // 4. Possibly change this.
 
   // Bounds-check failure.
-  check (s.(x + 6) == (0x0 as u8));
+  assert (s.(x + 6) == (0x0 as u8));
 }

src/test/run-fail/vec-overrun.rs

@@ -6,7 +6,7 @@
 fn main() {
   let vec[int] v = vec(10);
   let int x = 0;
-  check (v.(x) == 10);
+  assert (v.(x) == 10);
   // Bounds-check failure.
-  check (v.(x + 2) == 20);
+  assert (v.(x + 2) == 20);
 }

src/test/run-fail/vec-underrun.rs

@@ -6,7 +6,7 @@
 fn main() {
   let vec[int] v = vec(10, 20);
   let int x = 0;
-  check (v.(x) == 10);
+  assert (v.(x) == 10);
   // Bounds-check failure.
-  check (v.(x-1) == 20);
+  assert (v.(x-1) == 20);
 }

src/test/run-pass/alt-pattern-drop.rs

@@ -21,12 +21,12 @@ fn foo(str s) {
   }
 
   log _str.refcount(s);
-  check (_str.refcount(s) == const_refcount);
+  assert (_str.refcount(s) == const_refcount);
 }
 
 fn main() {
   let str s = "hi";     // ref up
   foo(s);               // ref up then down
   log _str.refcount(s);
-  check (_str.refcount(s) == const_refcount);
+  assert (_str.refcount(s) == const_refcount);
 }

src/test/run-pass/alt-pattern-lit.rs

@@ -12,6 +12,6 @@ fn altlit(int f) -> int {
 }
 
 fn main() {
-  check (altlit(10) == 20);
-  check (altlit(11) == 22);
+  assert (altlit(10) == 20);
+  assert (altlit(11) == 22);
 }

src/test/run-pass/alt-tag.rs

@@ -32,8 +32,8 @@ fn main() {
   let color gray = rgb(127, 127, 127);
   let color clear = rgba(50, 150, 250, 0);
   let color red = hsl(0, 255, 255);
-  check (process(gray) == 127);
-  check (process(clear) == 0);
-  check (process(red) == 255);
+  assert (process(gray) == 127);
+  assert (process(clear) == 0);
+  assert (process(red) == 255);
 }
 

src/test/run-pass/arith-0.rs

@@ -1,5 +1,5 @@
 fn main() -> () {
     let int a = 10;
     log a;
-    check (a * (a - 1) == 90);
+    assert (a * (a - 1) == 90);
 }

src/test/run-pass/arith-1.rs

@@ -1,22 +1,22 @@
 fn main() -> () {
     let int i32_a = 10;
-    check(i32_a == 10);
-    check(i32_a - 10 == 0);
-    check(i32_a / 10 == 1);
-    check(i32_a - 20 == -10);
-    check(i32_a << 10 == 10240);
-    check(i32_a << 16 == 655360);
-    check(i32_a * 16 == 160);
-    check(i32_a * i32_a * i32_a == 1000);
-    check(i32_a * i32_a * i32_a * i32_a == 10000);
-    check(((i32_a * i32_a) / i32_a) * i32_a == 100);
-    check(i32_a * (i32_a - 1) << 2 + i32_a == 368640);
+    assert (i32_a == 10);
+    assert (i32_a - 10 == 0);
+    assert (i32_a / 10 == 1);
+    assert (i32_a - 20 == -10);
+    assert (i32_a << 10 == 10240);
+    assert (i32_a << 16 == 655360);
+    assert (i32_a * 16 == 160);
+    assert (i32_a * i32_a * i32_a == 1000);
+    assert (i32_a * i32_a * i32_a * i32_a == 10000);
+    assert (((i32_a * i32_a) / i32_a) * i32_a == 100);
+    assert (i32_a * (i32_a - 1) << 2 + i32_a == 368640);
 
     let int i32_b = 0x10101010;
-    check(i32_b + 1 - 1 == i32_b);
-    check(i32_b << 1 == i32_b << 1);
-    check(i32_b >> 1 == i32_b >> 1);
-    check((i32_b & (i32_b << 1)) == 0);
+    assert (i32_b + 1 - 1 == i32_b);
+    assert (i32_b << 1 == i32_b << 1);
+    assert (i32_b >> 1 == i32_b >> 1);
+    assert ((i32_b & (i32_b << 1)) == 0);
     log ((i32_b | (i32_b << 1)));
-    check((i32_b | (i32_b << 1)) == 0x30303030);
+    assert ((i32_b | (i32_b << 1)) == 0x30303030);
 }

src/test/run-pass/arith-2.rs

@@ -1,5 +1,5 @@
 fn main() -> () {
     let int i32_c = 0x10101010;
-    check (i32_c + i32_c * 2 / 3 * 2 + (i32_c - 7 % 3) == 
+    assert (i32_c + i32_c * 2 / 3 * 2 + (i32_c - 7 % 3) == 
            i32_c + (((i32_c * 2) / 3) * 2) + (i32_c - (7 % 3)));
 }

src/test/run-pass/arith-unsigned.rs

@@ -2,24 +2,24 @@
 // Unsigned integer operations
 
 fn main() {
-  check (0u8 < 255u8);
-  check (0u8 <= 255u8);
-  check (255u8 > 0u8);
-  check (255u8 >= 0u8);
-  check (250u8 / 10u8 == 25u8);
-  check (255u8 % 10u8 == 5u8);
-  check (0u16 < 60000u16);
-  check (0u16 <= 60000u16);
-  check (60000u16 > 0u16);
-  check (60000u16 >= 0u16);
-  check (60000u16 / 10u16 == 6000u16);
-  check (60005u16 % 10u16 == 5u16);
-  check (0u32 < 4000000000u32);
-  check (0u32 <= 4000000000u32);
-  check (4000000000u32 > 0u32);
-  check (4000000000u32 >= 0u32);
-  check (4000000000u32 / 10u32 == 400000000u32);
-  check (4000000005u32 % 10u32 == 5u32);
+  assert (0u8 < 255u8);
+  assert (0u8 <= 255u8);
+  assert (255u8 > 0u8);
+  assert (255u8 >= 0u8);
+  assert (250u8 / 10u8 == 25u8);
+  assert (255u8 % 10u8 == 5u8);
+  assert (0u16 < 60000u16);
+  assert (0u16 <= 60000u16);
+  assert (60000u16 > 0u16);
+  assert (60000u16 >= 0u16);
+  assert (60000u16 / 10u16 == 6000u16);
+  assert (60005u16 % 10u16 == 5u16);
+  assert (0u32 < 4000000000u32);
+  assert (0u32 <= 4000000000u32);
+  assert (4000000000u32 > 0u32);
+  assert (4000000000u32 >= 0u32);
+  assert (4000000000u32 / 10u32 == 400000000u32);
+  assert (4000000005u32 % 10u32 == 5u32);
 
   // 64-bit numbers have some flakiness yet. Not tested
 }

src/test/run-pass/autoderef-full-lval.rs

@@ -8,11 +8,11 @@ fn main() {
   let clam b = rec(x=@10, y=@20);
   let int z = a.x + b.y;
   log z;
-  check (z == 21);
+  assert (z == 21);
 
   let fish forty = tup(@40);
   let fish two = tup(@2);
   let int answer = forty._0 + two._0;
   log answer;
-  check (answer == 42);
+  assert (answer == 42);
 }

src/test/run-pass/bind-exterior.rs

@@ -4,5 +4,5 @@ fn foo(@int a, @int b) -> int {
 
 fn main() {
   auto f1 = bind foo(@10, @12);
-  check(f1() == 22);
+  assert (f1() == 22);
 }

src/test/run-pass/bind-interior.rs

@@ -7,5 +7,5 @@ fn f(int n) -> int {
 fn main() {
   let fn() -> int g = bind f(10);
   let int i = g();
-  check(i == 10);
+  assert (i == 10);
 }

src/test/run-pass/bind-obj-ctor.rs

@@ -11,7 +11,7 @@ fn main() {
   auto ctor1 = bind simple(_, 2);
   auto obj1 = ctor0(2);
   auto obj2 = ctor1(1);
-  check (obj0.sum() == 3);
-  check (obj1.sum() == 3);
-  check (obj2.sum() == 3);
+  assert (obj0.sum() == 3);
+  assert (obj1.sum() == 3);
+  assert (obj2.sum() == 3);
 }

src/test/run-pass/bind-thunk.rs

@@ -7,5 +7,5 @@ fn f() -> int {
 fn main() {
   let fn() -> int g = bind f();
   let int i = g();
-  check(i == 42);
+  assert (i == 42);
 }

src/test/run-pass/bind-trivial.rs

@@ -7,5 +7,5 @@ fn f(int n) -> int {
 fn main() {
   let fn(int) -> int g = bind f(_);
   let int i = g(42);
-  check(i == 42);
+  assert (i == 42);
 }

src/test/run-pass/bitwise.rs

@@ -8,14 +8,14 @@ fn main() {
   a = a ^ b;
   log a;
   log b;
-  check (b == 1);
-  check (a == 2);
+  assert (b == 1);
+  assert (a == 2);
 
-  check (~(0xf0) & 0xff == 0xf);
-  check (0xf0 | 0xf == 0xff);
-  check (0xf << 4 == 0xf0);
-  check (0xf0 >> 4 == 0xf);
-  check (-16 >>> 2 == -4);
-  check (0b1010_1010 | 0b0101_0101 == 0xff);
+  assert (~(0xf0) & 0xff == 0xf);
+  assert (0xf0 | 0xf == 0xff);
+  assert (0xf << 4 == 0xf0);
+  assert (0xf0 >> 4 == 0xf);
+  assert (-16 >>> 2 == -4);
+  assert (0b1010_1010 | 0b0101_0101 == 0xff);
 }
 

src/test/run-pass/bool-not.rs

@@ -2,14 +2,14 @@
 
 fn main() {
   if (!false) {
-    check (true);
+    assert (true);
   } else {
-    check (false);
+    assert (false);
   }
 
   if (!true) {
-    check (false);
+    assert (false);
   } else {
-    check (true);
+    assert (true);
   }
 }

src/test/run-pass/box-compare.rs

@@ -1,6 +1,6 @@
 // xfail-boot
 fn main() {
-  check (@1 < @3);
-  check (@@"hello " > @@"hello");
-  check (@@@"hello" != @@@"there");
+  assert (@1 < @3);
+  assert (@@"hello " > @@"hello");
+  assert (@@@"hello" != @@@"there");
 }

src/test/run-pass/box-unbox.rs

@@ -6,5 +6,5 @@ fn main() {
   let int foo = 17;
   let box[int] bfoo = tup(@foo);
   log "see what's in our box";
-  check (unbox[int](bfoo) == foo);
+  assert (unbox[int](bfoo) == foo);
 }

src/test/run-pass/box.rs

@@ -1,4 +1,4 @@
 fn main() {
   let @int x = @10;
-  check ((*x) == 10);
+  assert ((*x) == 10);
 }

src/test/run-pass/break.rs

@@ -6,35 +6,35 @@ fn main() {
     i += 1;
     if (i == 10) { break; }
   }
-  check(i == 10);
+  assert (i == 10);
 
   do {
     i += 1;
     if (i == 20) { break; }
   } while (i < 30);
-  check(i == 20);
+  assert (i == 20);
 
   for (int x in vec(1, 2, 3, 4, 5, 6)) {
     if (x == 3) { break; }
-    check(x <= 3);
+    assert (x <= 3);
   }
 
   i = 0;
   while (i < 10) {
     i += 1;
     if (i % 2 == 0) { cont; }
-    check(i % 2 != 0);
+    assert (i % 2 != 0);
   }
 
   i = 0;
   do {
     i += 1;
     if (i % 2 == 0) { cont; }
-    check(i % 2 != 0);
+    assert (i % 2 != 0);
   } while (i < 10);
 
   for (int x in vec(1, 2, 3, 4, 5, 6)) {
     if (x % 2 == 0) { cont; }
-    check(x % 2 != 0);
+    assert (x % 2 != 0);
   }
 }

src/test/run-pass/cast.rs

@@ -3,14 +3,14 @@
 
 fn main() {
   let int i = 'Q' as int;
-  check (i == 0x51);
+  assert (i == 0x51);
   let u32 u = i as u32;
-  check (u == (0x51 as u32));
-  check (u == ('Q' as u32));
-  check ((i as u8) == ('Q' as u8));
-  check (((i as u8) as i8) == (('Q' as u8) as i8));
-  check ((0x51 as char) == 'Q');
+  assert (u == (0x51 as u32));
+  assert (u == ('Q' as u32));
+  assert ((i as u8) == ('Q' as u8));
+  assert (((i as u8) as i8) == (('Q' as u8) as i8));
+  assert ((0x51 as char) == 'Q');
 
-  check (true == (1 as bool));
-  check ((0 as u32) == (false as u32));
+  assert (true == (1 as bool));
+  assert ((0 as u32) == (false as u32));
 }

src/test/run-pass/char.rs

@@ -1,12 +1,12 @@
 fn main() {
     let char c = 'x';
     let char d = 'x';
-    check(c == 'x');
-    check('x' == c);
-    check(c == c);
-    check(c == d);
-    check(d == c);
-    check (d == 'x');
-    check('x' == d);
+    assert (c == 'x');
+    assert ('x' == c);
+    assert (c == c);
+    assert (c == d);
+    assert (d == c);
+    assert (d == 'x');
+    assert ('x' == d);
 }
 

src/test/run-pass/clone-with-exterior.rs

@@ -1,8 +1,8 @@
 // xfail-boot
 // xfail-stage0
 fn f(@rec(int a, int b) x) {
-  check (x.a == 10);
-  check (x.b == 12);
+  assert (x.a == 10);
+  assert (x.b == 12);
 }
 
 fn main() {

src/test/run-pass/comm.rs

@@ -8,7 +8,7 @@ fn main() {
   y <- p;
   log "received";
   log y;
-  check (y == 10);
+  assert (y == 10);
 }
 
 fn child(chan[int] c) {

src/test/run-pass/decl-with-recv.rs

@@ -6,9 +6,9 @@ fn main() {
 
   ch <| 10;
   let int i <- po;
-  check (i == 10);
+  assert (i == 10);
 
   ch <| 11;
   auto j <- po;
-  check (j == 11);
+  assert (j == 11);
 }

src/test/run-pass/deep.rs

@@ -10,5 +10,5 @@ fn f(int x) -> int {
 }
 
 fn main() {
-  check (f(5000) == 5000);
+  assert (f(5000) == 5000);
 }

src/test/run-pass/div-mod.rs

@@ -3,15 +3,15 @@
 fn main() {
   let int x = 15;
   let int y = 5;
-  check(x / 5 == 3);
-  check(x / 4 == 3);
-  check(x / 3 == 5);
-  check(x / y == 3);
-  check(15 / y == 3);
+  assert (x / 5 == 3);
+  assert (x / 4 == 3);
+  assert (x / 3 == 5);
+  assert (x / y == 3);
+  assert (15 / y == 3);
 
-  check(x % 5 == 0);
-  check(x % 4 == 3);
-  check(x % 3 == 0);
-  check(x % y == 0);
-  check(15 % y == 0);
+  assert (x % 5 == 0);
+  assert (x % 4 == 3);
+  assert (x % 3 == 0);
+  assert (x % y == 0);
+  assert (15 % y == 0);
 }

src/test/run-pass/else-if.rs

@@ -1,42 +1,42 @@
 fn main() {
   if (1 == 2) {
-    check(false);
+    assert (false);
   } else if (2 == 3) {
-    check(false);
+    assert (false);
   } else if (3 == 4) {
-    check(false);
+    assert (false);
   } else {
-    check(true);
+    assert (true);
   }
 
 
   if (1 == 2) {
-    check(false);
+    assert (false);
   } else if (2 == 2) {
-    check(true);
+    assert (true);
   }
 
   if (1 == 2) {
-    check(false);
+    assert (false);
   } else if (2 == 2) {
     if (1 == 1) {
-      check(true);
+      assert (true);
     } else {
       if (2 == 1) {
-        check(false);
+        assert (false);
       } else {
-        check(false);
+        assert (false);
       }
     }
   }
 
   if (1 == 2) {
-    check(false);
+    assert (false);
   } else {
     if (1 == 2) {
-      check(false);
+      assert (false);
     } else {
-      check(true);
+      assert (true);
     }
   }
 }

src/test/run-pass/expr-alt-box.rs

@@ -9,7 +9,7 @@ fn test_box() {
       @100
     }
   };
-  check (*res == 100);
+  assert (*res == 100);
 }
 
 fn test_str() {
@@ -18,7 +18,7 @@ fn test_str() {
       "happy"
     }
   };
-  check (res == "happy");
+  assert (res == "happy");
 }
 
 fn main() {

src/test/run-pass/expr-alt-generic-box1.rs

@@ -9,7 +9,7 @@ fn test_generic[T](@T expected, &compare[T] eq) {
       expected
     }
   };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_box() {

src/test/run-pass/expr-alt-generic-box2.rs

@@ -9,7 +9,7 @@ fn test_generic[T](&T expected, &compare[T] eq) {
       expected
     }
   };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_vec() {

src/test/run-pass/expr-alt-generic.rs

@@ -9,7 +9,7 @@ fn test_generic[T](&T expected, &compare[T] eq) {
       expected
     }
   };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_bool() {

src/test/run-pass/expr-alt-struct.rs

@@ -9,7 +9,7 @@ fn test_rec() {
       rec(i = 100)
     }
   };
-  check (res == rec(i = 100));
+  assert (res == rec(i = 100));
 }
 
 fn test_tag() {
@@ -26,7 +26,7 @@ fn test_tag() {
       sad
     }
   };
-  check (res == happy);
+  assert (res == happy);
 }
 
 fn main() {

src/test/run-pass/expr-alt.rs

@@ -12,7 +12,7 @@ fn test_basic() {
       false
     }
   };
-  check (res);
+  assert (res);
 
   res = alt(false) {
     case (true) {
@@ -22,7 +22,7 @@ fn test_basic() {
       true
     }
   };
-  check (res);
+  assert (res);
 }
 
 fn test_inferrence() {
@@ -34,7 +34,7 @@ fn test_inferrence() {
       false
     }
   };
-  check (res);
+  assert (res);
 }
 
 fn test_alt_as_alt_head() {
@@ -47,7 +47,7 @@ fn test_alt_as_alt_head() {
       true
     }
   };
-  check (res);
+  assert (res);
 }
 
 fn test_alt_as_block_result() {
@@ -66,7 +66,7 @@ fn test_alt_as_block_result() {
       }
     }
   };
-  check (res);
+  assert (res);
 }
 
 fn main() {

src/test/run-pass/expr-block-box.rs

@@ -6,5 +6,5 @@ fn main() {
     @100
   };
 
-  check (*x == 100);
+  assert (*x == 100);
 }

src/test/run-pass/expr-block-fn.rs

@@ -6,7 +6,7 @@ fn test_fn() {
     ret 10;
   }
   let t res = { ten };
-  check (res() == 10);
+  assert (res() == 10);
 }
 
 fn main() {

src/test/run-pass/expr-block-generic-box1.rs

@@ -5,7 +5,7 @@ type compare[T] = fn(@T t1, @T t2) -> bool;
 
 fn test_generic[T](@T expected, &compare[T] eq) {
   let @T actual = { expected };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_box() {

src/test/run-pass/expr-block-generic-box2.rs

@@ -5,7 +5,7 @@ type compare[T] = fn(&T t1, &T t2) -> bool;
 
 fn test_generic[T](&T expected, &compare[T] eq) {
   let T actual = { expected };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_vec() {

src/test/run-pass/expr-block-generic.rs

@@ -7,7 +7,7 @@ type compare[T] = fn(&T t1, &T t2) -> bool;
 
 fn test_generic[T](&T expected, &compare[T] eq) {
   let T actual = { expected };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_bool() {

src/test/run-pass/expr-block.rs

@@ -5,12 +5,12 @@
 
 fn test_basic() {
   let bool res = { true };
-  check (res);
+  assert (res);
 }
 
 fn test_rec() {
   auto res = { rec(v1 = 10, v2 = 20) };
-  check (res.v2 == 20);
+  assert (res.v2 == 20);
 }
 
 fn test_filled_with_stuff() {
@@ -21,7 +21,7 @@ fn test_filled_with_stuff() {
     }
     a
   };
-  check (res == 10);
+  assert (res == 10);
 }
 
 fn main() {

src/test/run-pass/expr-if-box.rs

@@ -5,12 +5,12 @@
 
 fn test_box() {
   auto res = if (true) { @100 } else { @101 };
-  check (*res == 100);
+  assert (*res == 100);
 }
 
 fn test_str() {
   auto res = if (true) { "happy" } else { "sad" };
-  check (res == "happy");
+  assert (res == "happy");
 }
 
 fn main() {

src/test/run-pass/expr-if-generic-box1.rs

@@ -5,7 +5,7 @@ type compare[T] = fn(@T t1, @T t2) -> bool;
 
 fn test_generic[T](@T expected, @T not_expected, &compare[T] eq) {
   let @T actual = if (true) { expected } else { not_expected };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_box() {

src/test/run-pass/expr-if-generic-box2.rs

@@ -5,7 +5,7 @@ type compare[T] = fn(&T t1, &T t2) -> bool;
 
 fn test_generic[T](&T expected, &T not_expected, &compare[T] eq) {
   let T actual = if (true) { expected } else { not_expected };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_vec() {

src/test/run-pass/expr-if-generic.rs

@@ -7,7 +7,7 @@ type compare[T] = fn(&T t1, &T t2) -> bool;
 
 fn test_generic[T](&T expected, &T not_expected, &compare[T] eq) {
   let T actual = if (true) { expected } else { not_expected };
-  check (eq(expected, actual));
+  assert (eq(expected, actual));
 }
 
 fn test_bool() {

src/test/run-pass/expr-if-struct.rs

@@ -5,7 +5,7 @@
 
 fn test_rec() {
   auto res = if (true) { rec(i = 100) } else { rec(i = 101) };
-  check (res == rec(i = 100));
+  assert (res == rec(i = 100));
 }
 
 fn test_tag() {
@@ -15,7 +15,7 @@ fn test_tag() {
   }
 
   auto res = if (true) { happy } else { sad };
-  check (res == happy);
+  assert (res == happy);
 }
 
 fn main() {

src/test/run-pass/expr-if.rs

@@ -5,12 +5,12 @@
 
 fn test_if() {
   let bool res = if (true) { true } else { false };
-  check (res);
+  assert (res);
 }
 
 fn test_else() {
   let bool res = if (false) { false } else { true };
-  check (res);
+  assert (res);
 }
 
 fn test_elseif1() {
@@ -21,7 +21,7 @@ fn test_elseif1() {
   } else {
     false
   };
-  check (res);
+  assert (res);
 }
 
 fn test_elseif2() {
@@ -32,7 +32,7 @@ fn test_elseif2() {
   } else {
     false
   };
-  check (res);
+  assert (res);
 }
 
 fn test_elseif3() {
@@ -43,12 +43,12 @@ fn test_elseif3() {
   } else {
     true
   };
-  check (res);
+  assert (res);
 }
 
 fn test_inferrence() {
   auto res = if (true) { true } else { false };
-  check (res);
+  assert (res);
 }
 
 fn test_if_as_if_condition() {
@@ -57,14 +57,14 @@ fn test_if_as_if_condition() {
   } else {
     false
   };
-  check (res1);
+  assert (res1);
 
   auto res2 = if (if (true) { false } else { true }) {
     false
   } else {
     true
   };
-  check (res2);
+  assert (res2);
 }
 
 fn test_if_as_block_result() {
@@ -77,7 +77,7 @@ fn test_if_as_block_result() {
   } else {
     false
   };
-  check (res);
+  assert (res);
 }
 
 fn main() {

src/test/run-pass/exterior.rs

@@ -3,16 +3,16 @@
 type point = rec(int x, int y, mutable int z);
 
 fn f(@point p) {
-  check (p.z == 12);
+  assert (p.z == 12);
   p.z = 13;
-  check (p.z == 13);
+  assert (p.z == 13);
 }
 
 fn main() {
   let point a = rec(x=10, y=11, mutable z=12);
   let @point b = @a;
-  check (b.z == 12);
+  assert (b.z == 12);
   f(b);
-  check (a.z == 12);
-  check (b.z == 13);
+  assert (a.z == 12);
+  assert (b.z == 13);
 }

src/test/run-pass/fact.rs

@@ -15,7 +15,7 @@ fn f(int x) -> int {
   }
 }
 fn main () {
-  check (f(5) == 120);
+  assert (f(5) == 120);
   // log "all done";
 }
 

src/test/run-pass/float2.rs

@@ -12,13 +12,13 @@ fn main() {
   auto j = 3.1e+9;
   auto k = 3.2e-10;
  
-  check(a == b);
-  check(c < b);
-  check(c == d);
-  check(e < g);
-  check(f < h);
-  check(g == 1000000.0f32);
-  check(h == i);
-  check(j > k);
-  check(k < a);
+  assert (a == b);
+  assert (c < b);
+  assert (c == d);
+  assert (e < g);
+  assert (f < h);
+  assert (g == 1000000.0f32);
+  assert (h == i);
+  assert (j > k);
+  assert (k < a);
 }

src/test/run-pass/floatlits.rs

@@ -1,9 +1,9 @@
 // xfail-boot
 fn main() {
   auto f = 4.999999999999;
-  check (f > 4.90);
-  check (f < 5.0);
+  assert (f > 4.90);
+  assert (f < 5.0);
   auto g = 4.90000000001e-10;
-  check(g > 5e-11);
-  check(g < 5e-9);
+  assert (g > 5e-11);
+  assert (g < 5e-9);
 }

src/test/run-pass/foreach-nested-2.rs

@@ -28,12 +28,12 @@ fn main() {
         }
     }
 
-    check (a.(0) == 0);
-    check (a.(1) == 1);
-    check (a.(2) == 10);
-    check (a.(3) == 11);
-    check (a.(4) == 100);
-    check (a.(5) == 101);
-    check (a.(6) == 110);
-    check (a.(7) == 111);
+    assert (a.(0) == 0);
+    assert (a.(1) == 1);
+    assert (a.(2) == 10);
+    assert (a.(3) == 11);
+    assert (a.(4) == 100);
+    assert (a.(5) == 101);
+    assert (a.(6) == 110);
+    assert (a.(7) == 111);
 }

src/test/run-pass/foreach-nested.rs

@@ -16,8 +16,8 @@ fn main() {
         }
     }
 
-    check (a.(0) == 0);
-    check (a.(1) == 1);
-    check (a.(2) == 10);
-    check (a.(3) == 11);
+    assert (a.(0) == 0);
+    assert (a.(1) == 1);
+    assert (a.(2) == 10);
+    assert (a.(3) == 11);
 }

src/test/run-pass/foreach-put-structured.rs

@@ -14,9 +14,9 @@ fn main() {
   for each (tup(int,int) p in pairs()) {
       log p._0;
       log p._1;
-      check (p._0 + 10 == i);
+      assert (p._0 + 10 == i);
       i += 1;
       j = p._1;
     }
-  check(j == 45);
+  assert (j == 45);
 }

src/test/run-pass/foreach-simple-outer-slot.rs

@@ -9,7 +9,7 @@ fn main() {
   }
   log "sum";
   log sum;
-  check (sum == 45);
+  assert (sum == 45);
 }
 
 iter first_ten() -> int {

src/test/run-pass/fun-call-variants.rs

@@ -13,7 +13,7 @@ fn main() {
   let int a = direct(3); // direct
   //let int b = ho(direct); // indirect unbound
   let int c = ho(bind direct(_)); // indirect bound
-  //check(a == b);
-  //check(b == c);
+  //assert (a == b);
+  //assert (b == c);
 }
 

src/test/run-pass/fun-indirect-call.rs

@@ -7,5 +7,5 @@ fn f() -> int {
 fn main() {
   let fn() -> int g = f;
   let int i = g();
-  check(i == 42);
+  assert (i == 42);
 }

src/test/run-pass/generic-alias-box.rs

@@ -8,5 +8,5 @@ fn main() {
   auto expected = @100;
   auto actual = id[@int](expected);
   log *actual;
-  check (*expected == *actual);
+  assert (*expected == *actual);
 }

src/test/run-pass/generic-bind-2.rs

@@ -5,7 +5,7 @@ fn id[T](&T t) -> T {
 
 fn main() {
   auto t = tup(1,2,3,4,5,6,7);
-  check (t._5 == 6);
+  assert (t._5 == 6);
   auto f0 = bind id[tup(int,int,int,int,int,int,int)](t);
-  check (f0()._5 == 6);
+  assert (f0()._5 == 6);
 }

src/test/run-pass/generic-bind.rs

@@ -4,7 +4,7 @@ fn id[T](&T t) -> T {
 
 fn main() {
   auto t = tup(1,2,3,4,5,6,7);
-  check (t._5 == 6);
+  assert (t._5 == 6);
   auto f1 = bind id[tup(int,int,int,int,int,int,int)](_);
-  check (f1(t)._5 == 6);
+  assert (f1(t)._5 == 6);
 }

src/test/run-pass/generic-box.rs

@@ -4,5 +4,5 @@ fn box[T](&tup(T,T,T) x) -> @tup(T,T,T) {
 
 fn main() {
   let @tup(int,int,int) x = box[int](tup(1,2,3));
-  check (x._1 == 2);
+  assert (x._1 == 2);
 }

src/test/run-pass/generic-derived-type.rs

@@ -12,6 +12,6 @@ fn main() {
   auto b = f[int](10);
   log b._0;
   log b._1;
-  check (b._0 == 10);
-  check (b._1 == 10);
+  assert (b._0 == 10);
+  assert (b._1 == 10);
 }

src/test/run-pass/generic-exterior-box.rs

@@ -8,6 +8,6 @@ fn main() {
   let int foo = 17;
   let tupbox[int] tbfoo = tuplift[int](foo);
   let recbox[int] rbfoo = reclift[int](foo);
-  check (tbfoo._0 == foo);
-  check (rbfoo.x == foo);
+  assert (tbfoo._0 == foo);
+  assert (rbfoo.x == foo);
 }