Cleanup for 'be' statement and comments about future typestate

2 files changed, 10 insertions, 13 deletions

diff --git a/src/comp/middle/trans.rs b/src/comp/middle/trans.rs
index 499ab027..45d54e6a 100644
--- a/src/comp/middle/trans.rs
+++ b/src/comp/middle/trans.rs
@@ -3129,7 +3129,10 @@ fn trans_ret(@block_ctxt cx, &option.t[@ast.expr] e) -> result {
 }
 
 fn trans_be(@block_ctxt cx, @ast.expr e) -> result {
-    // FIXME: So this isn't actually a tail call
+    // FIXME: This should be a typestate precondition
+    check 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));
 }
 
diff --git a/src/comp/middle/typeck.rs b/src/comp/middle/typeck.rs
index 7a2b0616..4c3903a7 100644
--- a/src/comp/middle/typeck.rs
+++ b/src/comp/middle/typeck.rs
@@ -1720,18 +1720,12 @@ fn check_stmt(&@fn_ctxt fcx, &@ast.stmt stmt) -> @ast.stmt {
         }
 
         case (ast.stmt_be(?expr)) {
-            alt (expr.node) {
-                case (ast.expr_call(_, _, _)) {
-                    auto expr_0 = check_expr(fcx, expr);
-                    auto expr_1 = demand_expr(fcx, fcx.ret_ty, expr_0);
-                    ret @fold.respan[ast.stmt_](stmt.span,
-                                                ast.stmt_be(expr_1));
-                }
-                case (_) {
-                    fcx.ccx.sess.err("Non-call expression in tail call");
-                    fail;
-                }
-            }
+            /* FIXME: prove instead of check */
+            check ast.is_call_expr(expr);
+            auto expr_0 = check_expr(fcx, expr);
+            auto expr_1 = demand_expr(fcx, fcx.ret_ty, expr_0);
+            ret @fold.respan[ast.stmt_](stmt.span,
+                                        ast.stmt_be(expr_1));
         }
 
         case (ast.stmt_log(?expr)) {