Send is no longer a subkind of copy. This allows for sendable, but non-copyable resources. Closes #2420.

2 files changed, 14 insertions, 8 deletions

diff --git a/src/rustc/middle/kind.rs b/src/rustc/middle/kind.rs
index e7c318b7da5..effa593109c 100644
--- a/src/rustc/middle/kind.rs
+++ b/src/rustc/middle/kind.rs
@@ -24,10 +24,12 @@ import freevars::freevar_entry;
 // types.
 
 fn kind_to_str(k: kind) -> str {
-    if k == kind_sendable() { "sendable" }
-    else if k == kind_copyable() { "copyable" }
-    else if k == kind_noncopyable() { "noncopyable" }
-    else { fail "unknown kind" }
+    alt (ty::kind_can_be_copied(k), ty::kind_can_be_sent(k)) {
+      (false, false) { "noncopyable" }
+      (false, true)  { "sendable" }
+      (true,  false) { "copyable" }
+      (true,  true)  { "copy-sendable" }
+    }
 }
 
 type rval_map = std::map::hashmap<node_id, ()>;
diff --git a/src/rustc/middle/ty.rs b/src/rustc/middle/ty.rs
index 998dc9d5951..52cee2fd07b 100644
--- a/src/rustc/middle/ty.rs
+++ b/src/rustc/middle/ty.rs
@@ -425,9 +425,9 @@ fn param_bounds_to_kind(bounds: param_bounds) -> kind {
     for vec::each(*bounds) {|bound|
         alt bound {
           bound_copy {
-            if kind != kind_sendable() { kind = kind_copyable(); }
+            kind = lower_kind(kind, kind_copyable());
           }
-          bound_send { kind = kind_sendable(); }
+          bound_send { kind = lower_kind(kind, kind_send_only()); }
           _ {}
         }
     }
@@ -1277,6 +1277,10 @@ fn kind_sendable() -> kind {
     kind_(KIND_MASK_COPY | KIND_MASK_SEND)
 }
 
+fn kind_send_only() -> kind {
+    kind_(KIND_MASK_SEND)
+}
+
 // Using these query functons is preferable to direct comparison or matching
 // against the kind constants, as we may modify the kind hierarchy in the
 // future.
@@ -1303,7 +1307,7 @@ fn kind_lteq(a: kind, b: kind) -> bool {
 }
 
 fn lower_kind(a: kind, b: kind) -> kind {
-    if kind_lteq(a, b) { a } else { b }
+    kind_(*a | *b)
 }
 
 #[test]
@@ -1402,7 +1406,7 @@ fn type_kind(cx: ctxt, ty: t) -> kind {
         }
         lowest
       }
-      ty_res(did, inner, tps) { kind_noncopyable() }
+      ty_res(did, inner, tps) { kind_send_only() }
       ty_param(_, did) {
           param_bounds_to_kind(cx.ty_param_bounds.get(did.node))
       }