---

yaml
---
r: 11418
b: refs/heads/master
c: 4acfcd8
h: refs/heads/master
v: v3

Author: catamorphism

[refs]

@@ -1,5 +1,5 @@
 ---
-refs/heads/master: cb2f43cbf4332ffe90b8963f1bdbaa85febe1b92
+refs/heads/master: 4acfcd8c2f9b35caf966a2d7a8e0a658bfe5d292
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: 4a81779abd786ff22d71434c6d9a5917ea4cdfff
 refs/heads/try: 2898dcc5d97da9427ac367542382b6239d9c0bbf

trunk/src/comp/middle/resolve.rs

@@ -681,9 +681,9 @@ fn resolve_constr(e: @env, c: @ast::constr, sc: scopes, _v: vt<scopes>) {
          e.def_map.insert(c.node.id, d);
        }
        _ {
-           e.sess.span_err(c.span,
-                           "Non-predicate in constraint: " +
-                           path_to_str(c.node.path));
+           let s = path_to_str(c.node.path);
+           e.sess.span_err(c.span, #fmt("%s is not declared pure. Try \
+             `pure fn %s` instead of `fn %s`.", s, s, s));
        }
     }
 }

trunk/src/test/compile-fail/not-a-pred.rs

@@ -1,5 +1,5 @@
 // -*- rust -*-
-// error-pattern: Non-predicate in constraint: lt
+// error-pattern: lt is not declared pure
 
 fn f(a: int, b: int) : lt(a, b) { }