libstd: Remove "dual impls" from the language and enforce coherence rules. r=brson

"Dual impls" are impls that are both type implementations and trait
implementations. They can lead to ambiguity and so this patch removes them
from the language.

This also enforces coherence rules. Without this patch, records can implement
traits not defined in the current crate. This patch fixes this, and updates
all of rustc to adhere to the new enforcement. Most of this patch is fixing
rustc to obey the coherence rules, which involves converting a bunch of records
to structs.

1 files changed, 3 insertions, 1 deletions

diff --git a/src/libcore/task/spawn.rs b/src/libcore/task/spawn.rs
index a5ab4af40be..0a2f6634214 100644
--- a/src/libcore/task/spawn.rs
+++ b/src/libcore/task/spawn.rs
@@ -74,8 +74,10 @@
 #[warn(deprecated_mode)];
 
 use cast;
+use container::Map;
+use oldcomm;
 use option;
-use pipes::{stream, Chan, Port};
+use pipes::{Chan, GenericChan, GenericPort, Port};
 use pipes;
 use prelude::*;
 use private;