diff --git a/src/comp/front/ast.rs b/src/comp/front/ast.rs
index 3588c61c824..957c9206c90 100644
--- a/src/comp/front/ast.rs
+++ b/src/comp/front/ast.rs
@@ -346,6 +346,8 @@ tag ty_ {
     ty_obj(vec[ty_method]);
     ty_path(path, ann);
     ty_type;
+    ty_ivec(@ty);   // interior vector
+    ty_istr;        // interior string
     ty_constr(@ty, vec[@constr]);
 }
 
diff --git a/src/comp/front/parser.rs b/src/comp/front/parser.rs
index b8ec6a8a749..29c356655af 100644
--- a/src/comp/front/parser.rs
+++ b/src/comp/front/parser.rs
@@ -485,6 +485,7 @@ fn parse_ty(&parser p) -> @ast::ty {
     else if (eat_word(p, "uint")) { t = ast::ty_uint; }
     else if (eat_word(p, "float")) { t = ast::ty_float; }
     else if (eat_word(p, "str")) { t = ast::ty_str; }
+    else if (eat_word(p, "istr")) { t = ast::ty_istr; }
     else if (eat_word(p, "char")) { t = ast::ty_char; }
     else if (eat_word(p, "task")) { t = ast::ty_task; }
     else if (eat_word(p, "i8")) { t = ast::ty_machine(common::ty_i8); }
@@ -570,6 +571,11 @@ fn parse_ty(&parser p) -> @ast::ty {
         t = ast::ty_chan(parse_ty(p));
         hi = p.get_hi_pos();
         expect(p, token::RBRACKET);
+    } else if (eat_word(p, "ivec")) {
+        expect(p, token::LBRACKET);
+        t = ast::ty_ivec(parse_ty(p));
+        hi = p.get_hi_pos();
+        expect(p, token::RBRACKET);
     } else if (eat_word(p, "mutable")) {
         p.get_session().span_warn(p.get_span(),
             "ignoring deprecated 'mutable' type constructor");