std: rewrite Hash to make it more generic

This patch merges IterBytes and Hash traits, which clears up the
confusion of using `#[deriving(IterBytes)]` to support hashing.
Instead, it now is much easier to use the new `#[deriving(Hash)]`
for making a type hashable with a stream hash.

Furthermore, it supports custom non-stream-based hashers, such as
if a value's hash was cached in a database.

This does not yet replace the old IterBytes-hash with this new
version.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/libsyntax/util/interner.rs b/src/libsyntax/util/interner.rs
index aedff2d7854..1c801f7d970 100644
--- a/src/libsyntax/util/interner.rs
+++ b/src/libsyntax/util/interner.rs
@@ -17,6 +17,7 @@ use ast::Name;
 use std::cast;
 use std::cell::RefCell;
 use std::cmp::Equiv;
+use std::hash_old::Hash;
 use std::hashmap::HashMap;
 use std::rc::Rc;