librustc: Stop parsing `impl Type : Trait` and fix several declarations that slipped through. r=tjc

3 files changed, 14 insertions, 11 deletions

diff --git a/src/libsyntax/parse/lexer.rs b/src/libsyntax/parse/lexer.rs
index cb9382ebbb6..92c4f1e828f 100644
--- a/src/libsyntax/parse/lexer.rs
+++ b/src/libsyntax/parse/lexer.rs
@@ -127,7 +127,7 @@ impl reader for StringReader {
     fn dup(@mut self) -> reader { dup_string_reader(self) as reader }
 }
 
-pub impl TtReader: reader {
+pub impl reader for TtReader {
     fn is_eof(@mut self) -> bool { self.cur_tok == token::EOF }
     fn next_token(@mut self) -> TokenAndSpan { tt_next_token(self) }
     fn fatal(@mut self, m: ~str) -> ! {
diff --git a/src/libsyntax/parse/obsolete.rs b/src/libsyntax/parse/obsolete.rs
index 1b4493b7ec9..bf04996838c 100644
--- a/src/libsyntax/parse/obsolete.rs
+++ b/src/libsyntax/parse/obsolete.rs
@@ -45,10 +45,11 @@ pub enum ObsoleteSyntax {
     ObsoleteMoveInit,
     ObsoleteBinaryMove,
     ObsoleteUnsafeBlock,
-    ObsoleteUnenforcedBound
+    ObsoleteUnenforcedBound,
+    ObsoleteImplSyntax
 }
 
-pub impl ObsoleteSyntax: to_bytes::IterBytes {
+pub impl to_bytes::IterBytes for ObsoleteSyntax {
     #[inline(always)]
     pure fn iter_bytes(&self, +lsb0: bool, f: to_bytes::Cb) {
         (*self as uint).iter_bytes(lsb0, f);
@@ -115,6 +116,10 @@ pub impl Parser {
                 "unenforced type parameter bound",
                 "use trait bounds on the functions that take the type as \
                  arguments, not on the types themselves"
+            ),
+            ObsoleteImplSyntax => (
+                "colon-separated impl syntax",
+                "write `impl Trait for Type`"
             )
         };
 
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index b4fd7a5d2e8..15258a6bbee 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -74,7 +74,7 @@ use parse::obsolete::{ObsoleteLet, ObsoleteFieldTerminator};
 use parse::obsolete::{ObsoleteMoveInit, ObsoleteBinaryMove};
 use parse::obsolete::{ObsoleteStructCtor, ObsoleteWith};
 use parse::obsolete::{ObsoleteSyntax, ObsoleteLowerCaseKindBounds};
-use parse::obsolete::{ObsoleteUnsafeBlock};
+use parse::obsolete::{ObsoleteUnsafeBlock, ObsoleteImplSyntax};
 use parse::prec::{as_prec, token_to_binop};
 use parse::token::{can_begin_expr, is_ident, is_ident_or_path};
 use parse::token::{is_plain_ident, INTERPOLATED, special_idents};
@@ -2829,16 +2829,11 @@ pub impl Parser {
         // XXX: clownshoes
         let ident = special_idents::clownshoes_extensions;
 
-        // Parse the type. (If this is `impl trait for type`, however, this
-        // actually parses the trait.)
+        // Parse the trait.
         let mut ty = self.parse_ty(false);
 
         // Parse traits, if necessary.
-        let opt_trait = if self.token == token::COLON {
-            // Old-style trait.
-            self.bump();
-            Some(self.parse_trait_ref())
-        } else if self.eat_keyword(~"for") {
+        let opt_trait = if self.eat_keyword(~"for") {
             // New-style trait. Reinterpret the type as a trait.
             let opt_trait_ref = match ty.node {
                 ty_path(path, node_id) => {
@@ -2855,6 +2850,9 @@ pub impl Parser {
 
             ty = self.parse_ty(false);
             opt_trait_ref
+        } else if self.eat(token::COLON) {
+            self.obsolete(copy self.span, ObsoleteImplSyntax);
+            Some(self.parse_trait_ref())
         } else {
             None
         };