Check in a forgotten new file

This commit is contained in:
Marijn Haverbeke 2012-03-26 12:54:06 +02:00
parent 87e097a853
commit b89a5af2ab
1 changed files with 54 additions and 0 deletions

View File

@ -0,0 +1,54 @@
import syntax::ast::*;
import syntax::visit;
import driver::session::session;
type ctx = {in_loop: bool, can_ret: bool};
fn check_crate(sess: session, crate: @crate) {
visit::visit_crate(*crate, {in_loop: false,can_ret: true}, visit::mk_vt(@{
visit_item: {|i, _cx, v|
visit::visit_item(i, {in_loop: false, can_ret: true}, v);
},
visit_expr: {|e: @expr, cx: ctx, v: visit::vt<ctx>|
alt e.node {
expr_for(_, e, b) | expr_while(e, b) | expr_do_while(b, e) {
v.visit_expr(e, cx, v);
v.visit_block(b, {in_loop: true with cx}, v);
}
expr_loop(b) {
v.visit_block(b, {in_loop: true with cx}, v);
}
expr_fn(_, _, _, _) {
visit::visit_expr(e, {in_loop: false, can_ret: true}, v);
}
expr_fn_block(fn_decl, blk) {
visit::visit_expr(e, {in_loop: false, can_ret: false}, v);
}
expr_break {
if !cx.in_loop {
sess.span_err(e.span, "`break` outside of loop");
}
}
expr_cont {
if !cx.in_loop {
sess.span_err(e.span, "`cont` outside of loop");
}
}
expr_ret(oe) {
if !cx.can_ret {
sess.span_err(e.span, "`ret` in block function");
}
visit::visit_expr_opt(oe, cx, v);
}
expr_be(re) {
if !cx.can_ret {
sess.span_err(e.span, "`be` in block function");
}
v.visit_expr(re, cx, v);
}
_ { visit::visit_expr(e, cx, v); }
}
}
with *visit::default_visitor()
}));
}