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. 

5 files changed, 30 insertions, 0 deletions

diff --git a/src/libstd/num/f32.rs b/src/libstd/num/f32.rs
index 899d6236aaa..0addcce3eb6 100644
--- a/src/libstd/num/f32.rs
+++ b/src/libstd/num/f32.rs
@@ -12,6 +12,7 @@
 #[allow(missing_doc)];
 #[allow(non_uppercase_statics)];
 
+use default::Default;
 use libc::c_int;
 use num::{Zero, One, strconv};
 use num::{FPCategory, FPNaN, FPInfinite , FPZero, FPSubnormal, FPNormal};
@@ -237,6 +238,11 @@ impl Orderable for f32 {
     }
 }
 
+impl Default for f32 {
+    #[inline]
+    fn default() -> f32 { 0.0 }
+}
+
 impl Zero for f32 {
     #[inline]
     fn zero() -> f32 { 0.0 }
diff --git a/src/libstd/num/f64.rs b/src/libstd/num/f64.rs
index 6ab8350a115..b0675278238 100644
--- a/src/libstd/num/f64.rs
+++ b/src/libstd/num/f64.rs
@@ -13,6 +13,7 @@
 #[allow(missing_doc)];
 #[allow(non_uppercase_statics)];
 
+use default::Default;
 use libc::c_int;
 use num::{Zero, One, strconv};
 use num::{FPCategory, FPNaN, FPInfinite , FPZero, FPSubnormal, FPNormal};
@@ -260,6 +261,11 @@ impl Orderable for f64 {
     }
 }
 
+impl Default for f64 {
+    #[inline]
+    fn default() -> f64 { 0.0 }
+}
+
 impl Zero for f64 {
     #[inline]
     fn zero() -> f64 { 0.0 }
diff --git a/src/libstd/num/float.rs b/src/libstd/num/float.rs
index df26fadae16..3952f5478f7 100644
--- a/src/libstd/num/float.rs
+++ b/src/libstd/num/float.rs
@@ -23,6 +23,7 @@
 #[allow(missing_doc)];
 #[allow(non_uppercase_statics)];
 
+use default::Default;
 use num::{Zero, One, strconv};
 use num::FPCategory;
 use num;
@@ -382,6 +383,11 @@ impl Orderable for float {
     }
 }
 
+impl Default for float {
+    #[inline]
+    fn default() -> float { 0.0 }
+}
+
 impl Zero for float {
     #[inline]
     fn zero() -> float { 0.0 }
diff --git a/src/libstd/num/int_macros.rs b/src/libstd/num/int_macros.rs
index 07cafb0a4f1..ae2a56b835d 100644
--- a/src/libstd/num/int_macros.rs
+++ b/src/libstd/num/int_macros.rs
@@ -16,6 +16,7 @@ macro_rules! int_module (($T:ty, $bits:expr) => (mod generated {
 
 #[allow(non_uppercase_statics)];
 
+use default::Default;
 use num::{ToStrRadix, FromStrRadix};
 use num::{CheckedDiv, Zero, One, strconv};
 use prelude::*;
@@ -167,6 +168,11 @@ impl Orderable for $T {
     }
 }
 
+impl Default for $T {
+    #[inline]
+    fn default() -> $T { 0 }
+}
+
 impl Zero for $T {
     #[inline]
     fn zero() -> $T { 0 }
diff --git a/src/libstd/num/uint_macros.rs b/src/libstd/num/uint_macros.rs
index effeb60fc22..3deb7312b04 100644
--- a/src/libstd/num/uint_macros.rs
+++ b/src/libstd/num/uint_macros.rs
@@ -16,6 +16,7 @@ macro_rules! uint_module (($T:ty, $T_SIGNED:ty, $bits:expr) => (mod generated {
 
 #[allow(non_uppercase_statics)];
 
+use default::Default;
 use num::BitCount;
 use num::{ToStrRadix, FromStrRadix};
 use num::{CheckedDiv, Zero, One, strconv};
@@ -172,6 +173,11 @@ impl Orderable for $T {
     }
 }
 
+impl Default for $T {
+    #[inline]
+    fn default() -> $T { 0 }
+}
+
 impl Zero for $T {
     #[inline]
     fn zero() -> $T { 0 }