Remove references to @trait from a compiler error message

Author: lilyball

src/librustc/middle/typeck/astconv.rs

@@ -572,9 +572,8 @@ pub fn ast_ty_to_ty<AC:AstConv, RS:RegionScope>(
                         let path_str = path_to_str(path);
                         tcx.sess.span_err(
                             ast_ty.span,
-                            format!("reference to trait `{}` where a type is expected; \
-                                    try `@{}`, `~{}`, or `&{}`",
-                                    path_str, path_str, path_str, path_str));
+                            format!("reference to trait `{name}` where a type is expected; \
+                                    try `~{name}` or `&{name}`", name=path_str));
                         ty::mk_err()
                     }
                     ast::DefTy(did) | ast::DefStruct(did) => {

src/test/compile-fail/issue-5883.rs

@@ -11,13 +11,15 @@
 trait A {}
 
 struct Struct {
-    r: A //~ ERROR reference to trait `A` where a type is expected
+    r: A //~ ERROR reference to trait `A` where a type is expected; try `~A` or `&A`
 }
 
-fn new_struct(r: A) -> Struct { //~ ERROR reference to trait `A` where a type is expected
+fn new_struct(r: A) -> Struct {
+    //~^ ERROR reference to trait `A` where a type is expected; try `~A` or `&A`
     Struct { r: r }
 }
 
 trait Curve {}
-enum E {X(Curve)} //~ ERROR reference to trait `Curve` where a type is expected
+enum E {X(Curve)}
+//~^ ERROR reference to trait `Curve` where a type is expected; try `~Curve` or `&Curve`
 fn main() {}

src/test/compile-fail/regions-trait-2.rs

@@ -29,7 +29,7 @@ fn make_gc() -> @get_ctxt  {
     let ctxt = ctxt { v: 22u };
     let hc = has_ctxt { c: &ctxt };
     return @hc as @get_ctxt;
-    //^~ ERROR source contains reference
+    //~^ ERROR source contains reference
 }
 
 fn main() {

src/test/compile-fail/trait-bounds-not-on-bare-trait.rs

@@ -13,7 +13,8 @@ trait Foo {
 
 // This should emit the less confusing error, not the more confusing one.
 
-fn foo(_x: Foo:Send) { //~ERROR reference to trait `Foo` where a type is expected
+fn foo(_x: Foo:Send) {
+    //~^ERROR reference to trait `Foo` where a type is expected; try `~Foo` or `&Foo`
 }
 
 fn main() { }