First step for supporting "case (foo.bar(?zed))": Change the ast of

pat_tag to hold a path.

src/comp/front/ast.rs

@@ -55,7 +55,7 @@ type pat = spanned[pat_];
 tag pat_ {
     pat_wild(ann);
     pat_bind(ident, def_id, ann);
-    pat_tag(ident, vec[@pat], option.t[variant_def], ann);
+    pat_tag(path, vec[@pat], option.t[variant_def], ann);
 }
 
 tag mutability {

src/comp/front/parser.rs

@@ -1071,7 +1071,7 @@ impure fn parse_pat(parser p) -> @ast.pat {
             }
         }
         case (token.IDENT(?id)) {
-            p.bump();
+            auto tag_path = parse_path(p, GREEDY);
 
             let vec[@ast.pat] args;
             alt (p.peek()) {
@@ -1083,7 +1083,8 @@ impure fn parse_pat(parser p) -> @ast.pat {
                 case (_) { args = vec(); }
             }
 
-            pat = ast.pat_tag(id, args, none[ast.variant_def], ast.ann_none);
+            pat = ast.pat_tag(tag_path, args, none[ast.variant_def],
+                              ast.ann_none);
         }
         case (?tok) {
             p.err("expected pattern but found " + token.to_str(tok));