auto merge of #9115 : erickt/rust/master, r=erickt

This is a series of patches to modernize option and result. The highlights are:

* rename `.unwrap_or_default(value)` and etc to `.unwrap_or(value)`
* add `.unwrap_or_default()` that uses the `Default` trait
* add `Default` implementations for vecs, HashMap, Option
* add  `Option.and(T) -> Option<T>`, `Option.and_then(&fn() -> Option<T>) -> Option<T>`, `Option.or(T) -> Option<T>`, and `Option.or_else(&fn() -> Option<T>) -> Option<T>`
* add `option::ToOption`, `option::IntoOption`, `option::AsOption`, `result::ToResult`, `result::IntoResult`, `result::AsResult`, `either::ToEither`, and `either::IntoEither`, `either::AsEither`
* renamed `Option::chain*` and `Result::chain*` to `and_then` and `or_else` to avoid the eventual collision with `Iterator.chain`.
* Added a bunch of impls of `Default`
* Added a `#[deriving(Default)]` syntax extension
* Removed impls of `Zero` for `Option<T>` and vecs. 

1 files changed, 2 insertions, 2 deletions

diff --git a/src/librustpkg/version.rs b/src/librustpkg/version.rs
index c2d87ddeb82..6eb4cc56a2b 100644
--- a/src/librustpkg/version.rs
+++ b/src/librustpkg/version.rs
@@ -118,7 +118,7 @@ pub fn try_getting_local_version(local_path: &Path) -> Option<Version> {
         if !l.is_whitespace() {
             output = Some(l);
         }
-        match output.chain(try_parsing_version) {
+        match output.and_then(try_parsing_version) {
             Some(v) => return Some(v),
             None    => ()
         }
@@ -158,7 +158,7 @@ pub fn try_getting_version(remote_path: &Path) -> Option<Version> {
                 }
             }
 
-            output.chain(try_parsing_version)
+            output.and_then(try_parsing_version)
         }
         else {
             None