Polymorphic protocols work well enough to do MapReduce.

I did some horrible things with type variable naming here. It should do the right thing in most cases, but we'll need to go through and make it correct someday.

Author: eholk

src/libsyntax/ext/pipes/pipec.rs

@@ -319,11 +319,12 @@ impl compile of gen_init for protocol {
     }
 
     fn buffer_ty_path(cx: ext_ctxt) -> @ast::ty {
-        let mut params = ~[];
+        let mut params: ~[ast::ty_param] = ~[];
         for (copy self.states).each |s| {
             for s.ty_params.each |tp| {
-                if !params.contains(tp) {
-                    vec::push(params, tp);
+                alt params.find(|tpp| *tp.ident == *tpp.ident) {
+                  none { vec::push(params, tp) }
+                  _ { }
                 }
             }
         }
@@ -334,11 +335,12 @@ impl compile of gen_init for protocol {
 
     fn gen_buffer_type(cx: ext_ctxt) -> @ast::item {
         let ext_cx = cx;
-        let mut params = ~[];
+        let mut params: ~[ast::ty_param] = ~[];
         let fields = do (copy self.states).map_to_vec |s| {
             for s.ty_params.each |tp| {
-                if !params.contains(tp) {
-                    vec::push(params, tp);
+                alt params.find(|tpp| *tp.ident == *tpp.ident) {
+                  none { vec::push(params, tp) }
+                  _ { }
                 }
             }
             let ty = s.to_ty(cx);

src/test/bench/task-perf-word-count-generic.rs

@@ -143,14 +143,12 @@ mod map_reduce {
     proto! ctrl_proto {
         open: send<K: copy send, V: copy send> {
             find_reducer(K) -> reducer_response<K, V>,
-            mapper_done -> terminated
+            mapper_done -> !
         }
 
         reducer_response: recv<K: copy send, V: copy send> {
             reducer(chan<reduce_proto<V>>) -> open<K, V>
         }
-
-        terminated: send { }
     }
 
     enum reduce_proto<V: copy send> { emit_val(V), done, ref, release }
@@ -261,7 +259,7 @@ mod map_reduce {
         while num_mappers > 0 {
             let (_ready, message, ctrls) = pipes::select(ctrl);
             alt option::unwrap(message) {
-              ctrl_proto::mapper_done(_) {
+              ctrl_proto::mapper_done {
                 // #error("received mapper terminated.");
                 num_mappers -= 1;
                 ctrl = ctrls;