libsyntax: Remove ~fn() from the language

Author: pcwalton

src/libsyntax/parse/obsolete.rs

@@ -41,7 +41,8 @@ pub enum ObsoleteSyntax {
     ObsoleteLoopAsContinue,
     ObsoleteEnumWildcard,
     ObsoleteStructWildcard,
-    ObsoleteVecDotDotWildcard
+    ObsoleteVecDotDotWildcard,
+    ObsoleteBoxedClosure,
 }
 
 impl to_bytes::IterBytes for ObsoleteSyntax {
@@ -128,6 +129,11 @@ impl ParserObsoleteMethods for Parser {
                 "vec slice wildcard",
                 "use `..` instead of `.._` for matching slices"
             ),
+            ObsoleteBoxedClosure => (
+                "managed or owned closure",
+                "managed closures have been removed and owned closures are \
+                 now written `proc()`"
+            ),
         };
 
         self.report(sp, kind, kind_str, desc);

src/libsyntax/parse/parser.rs

@@ -1273,15 +1273,17 @@ impl Parser {
     pub fn parse_box_or_uniq_pointee(&self,
                                      sigil: ast::Sigil,
                                      ctor: &fn(v: mt) -> ty_) -> ty_ {
-        // ~'foo fn() or ~fn() are parsed directly as fn types:
+        // ~'foo fn() or ~fn() are parsed directly as obsolete fn types:
         match *self.token {
             token::LIFETIME(*) => {
                 let lifetime = self.parse_lifetime();
+                self.obsolete(*self.last_span, ObsoleteBoxedClosure);
                 return self.parse_ty_closure(Some(sigil), Some(lifetime));
             }
 
-            token::IDENT(*) => {
+            token::IDENT(*) if sigil == ast::BorrowedSigil => {
                 if self.token_is_old_style_closure_keyword() {
+                    self.obsolete(*self.last_span, ObsoleteBoxedClosure);
                     return self.parse_ty_closure(Some(sigil), None);
                 }
             }

src/test/compile-fail/issue-8615.rs

@@ -16,7 +16,7 @@ extern mod extra;
 use extra::arc;
 use std::util;
 
-fn foo(blk: ~once fn()) {
+fn foo(blk: proc()) {
     blk();
     blk(); //~ ERROR use of moved value
 }

src/test/compile-fail/once-cant-call-twice-on-heap.rs

@@ -17,7 +17,7 @@ extern mod extra;
 use extra::arc;
 use std::util;
 
-fn foo(blk: ~once fn()) {
+fn foo(blk: proc()) {
     blk();
 }