implement Ord, TotalEq and TotalOrd for char

Closes #6063

3 files changed, 56 insertions, 69 deletions

diff --git a/src/libcore/char.rs b/src/libcore/char.rs
index 8af61dcb861..ef2bd91e973 100644
--- a/src/libcore/char.rs
+++ b/src/libcore/char.rs
@@ -10,6 +10,7 @@
 
 //! Utilities for manipulating the char type
 
+use cmp::Ord;
 use option::{None, Option, Some};
 use str;
 use u32;
@@ -243,26 +244,26 @@ pub fn len_utf8_bytes(c: char) -> uint {
     else { fail!(~"invalid character!") }
 }
 
-/**
- * Compare two chars
- *
- * # Return value
- *
- * -1 if a < b, 0 if a == b, +1 if a > b
- */
-#[inline(always)]
-pub fn cmp(a: char, b: char) -> int {
-    return  if b > a { -1 }
-    else if b < a { 1 }
-    else { 0 }
-}
-
 #[cfg(notest)]
 impl Eq for char {
+    #[inline(always)]
     fn eq(&self, other: &char) -> bool { (*self) == (*other) }
+    #[inline(always)]
     fn ne(&self, other: &char) -> bool { (*self) != (*other) }
 }
 
+#[cfg(notest)]
+impl Ord for char {
+    #[inline(always)]
+    fn lt(&self, other: &char) -> bool { *self < *other }
+    #[inline(always)]
+    fn le(&self, other: &char) -> bool { *self <= *other }
+    #[inline(always)]
+    fn gt(&self, other: &char) -> bool { *self > *other }
+    #[inline(always)]
+    fn ge(&self, other: &char) -> bool { *self >= *other }
+}
+
 #[test]
 fn test_is_lowercase() {
     assert!(is_lowercase('a'));
diff --git a/src/libcore/cmp.rs b/src/libcore/cmp.rs
index b5a5ed7c9f4..b933b60a39f 100644
--- a/src/libcore/cmp.rs
+++ b/src/libcore/cmp.rs
@@ -64,6 +64,8 @@ totaleq_impl!(i64)
 totaleq_impl!(int)
 totaleq_impl!(uint)
 
+totaleq_impl!(char)
+
 #[deriving(Clone, Eq)]
 pub enum Ordering { Less = -1, Equal = 0, Greater = 1 }
 
@@ -116,6 +118,8 @@ totalord_impl!(i64)
 totalord_impl!(int)
 totalord_impl!(uint)
 
+totalord_impl!(char)
+
 pub fn cmp2<A:TotalOrd,B:TotalOrd>(
     a1: &A, b1: &B,
     a2: &A, b2: &B) -> Ordering
diff --git a/src/libstd/rope.rs b/src/libstd/rope.rs
index 33bc393e470..a5793462327 100644
--- a/src/libstd/rope.rs
+++ b/src/libstd/rope.rs
@@ -33,11 +33,7 @@
  * * access to a character by index is logarithmic (linear in strings);
  */
 
-use core::option;
 use core::prelude::*;
-use core::str;
-use core::uint;
-use core::vec;
 
 /// The type of ropes.
 pub type Rope = node::Root;
@@ -215,8 +211,8 @@ pub fn bal(rope:Rope) -> Rope {
     match (rope) {
       node::Empty => return rope,
       node::Content(x) => match (node::bal(x)) {
-        option::None    => rope,
-        option::Some(y) => node::Content(y)
+        None    => rope,
+        Some(y) => node::Content(y)
       }
     }
 }
@@ -558,13 +554,7 @@ pub fn char_at(rope: Rope, pos: uint) -> char {
 pub mod node {
     use rope::node;
 
-    use core::cast;
-    use core::char;
-    use core::option;
     use core::prelude::*;
-    use core::str;
-    use core::uint;
-    use core::vec;
 
     /// Implementation of type `rope`
     pub enum Root {
@@ -835,8 +825,8 @@ pub mod node {
             let mut it = leaf_iterator::start(node);
             loop {
                 match leaf_iterator::next(&mut it) {
-                  option::None => break,
-                  option::Some(x) => {
+                  None => break,
+                  Some(x) => {
                     //FIXME (#2744): Replace with memcpy or something similar
                     let local_buf: ~[u8] = cast::transmute(*x.content);
                     let mut i = x.byte_offset;
@@ -885,24 +875,24 @@ pub mod node {
      *
      * # Return value
      *
-     * * `option::None` if no transformation happened
-     * * `option::Some(x)` otherwise, in which case `x` has the same contents
+     * * `None` if no transformation happened
+     * * `Some(x)` otherwise, in which case `x` has the same contents
      *    as `node` bot lower height and/or fragmentation.
      */
     pub fn bal(node: @Node) -> Option<@Node> {
-        if height(node) < hint_max_node_height { return option::None; }
+        if height(node) < hint_max_node_height { return None; }
         //1. Gather all leaves as a forest
         let mut forest = ~[];
         let mut it = leaf_iterator::start(node);
         loop {
             match leaf_iterator::next(&mut it) {
-              option::None    => break,
-              option::Some(x) => forest.push(@Leaf(x))
+              None    => break,
+              Some(x) => forest.push(@Leaf(x))
             }
         }
         //2. Rebuild tree from forest
         let root = @*tree_from_forest_destructive(forest);
-        return option::Some(root);
+        return Some(root);
 
     }
 
@@ -1061,14 +1051,14 @@ pub mod node {
         while result == 0 {
             match (char_iterator::next(&mut ita), char_iterator::next(&mut itb))
             {
-              (option::None, option::None) => break,
-              (option::Some(chara), option::Some(charb)) => {
-                result = char::cmp(chara, charb);
+              (None, None) => break,
+              (Some(chara), Some(charb)) => {
+                result = chara.cmp(&charb) as int;
               }
-              (option::Some(_), _) => {
+              (Some(_), _) => {
                 result = 1;
               }
-              (_, option::Some(_)) => {
+              (_, Some(_)) => {
                 result = -1;
               }
             }
@@ -1145,9 +1135,7 @@ pub mod node {
     pub mod leaf_iterator {
         use rope::node::{Concat, Leaf, Node, height};
 
-        use core::option;
         use core::prelude::*;
-        use core::vec;
 
         pub struct T {
             stack: ~[@Node],
@@ -1168,7 +1156,7 @@ pub mod node {
         }
 
         pub fn next(it: &mut T) -> Option<Leaf> {
-            if it.stackpos < 0 { return option::None; }
+            if it.stackpos < 0 { return None; }
             loop {
                 let current = it.stack[it.stackpos];
                 it.stackpos -= 1;
@@ -1179,7 +1167,7 @@ pub mod node {
                     it.stackpos += 1;
                     it.stack[it.stackpos] = x.left;
                   }
-                  Leaf(x) => return option::Some(x)
+                  Leaf(x) => return Some(x)
                 }
             };
         }
@@ -1189,9 +1177,7 @@ pub mod node {
         use rope::node::{Leaf, Node};
         use rope::node::leaf_iterator;
 
-        use core::option;
         use core::prelude::*;
-        use core::str;
 
         pub struct T {
             leaf_iterator: leaf_iterator::T,
@@ -1202,7 +1188,7 @@ pub mod node {
         pub fn start(node: @Node) -> T {
             T {
                 leaf_iterator: leaf_iterator::start(node),
-                leaf: option::None,
+                leaf: None,
                 leaf_byte_pos: 0u,
             }
         }
@@ -1210,7 +1196,7 @@ pub mod node {
         pub fn empty() -> T {
             T {
                 leaf_iterator: leaf_iterator::empty(),
-                leaf:  option::None,
+                leaf: None,
                 leaf_byte_pos: 0u,
             }
         }
@@ -1218,12 +1204,12 @@ pub mod node {
         pub fn next(it: &mut T) -> Option<char> {
             loop {
                 match get_current_or_next_leaf(it) {
-                  option::None => return option::None,
-                  option::Some(_) => {
+                  None => return None,
+                  Some(_) => {
                     let next_char = get_next_char_in_leaf(it);
                     match next_char {
-                      option::None => loop,
-                      option::Some(_) => return next_char
+                      None => loop,
+                      Some(_) => return next_char
                     }
                   }
                 }
@@ -1232,12 +1218,12 @@ pub mod node {
 
         pub fn get_current_or_next_leaf(it: &mut T) -> Option<Leaf> {
             match it.leaf {
-              option::Some(_) => return it.leaf,
-              option::None => {
+              Some(_) => return it.leaf,
+              None => {
                 let next = leaf_iterator::next(&mut it.leaf_iterator);
                 match next {
-                  option::None => return option::None,
-                  option::Some(_) => {
+                  None => return None,
+                  Some(_) => {
                     it.leaf          = next;
                     it.leaf_byte_pos = 0u;
                     return next;
@@ -1249,12 +1235,12 @@ pub mod node {
 
         pub fn get_next_char_in_leaf(it: &mut T) -> Option<char> {
             match copy it.leaf {
-              option::None => return option::None,
-              option::Some(aleaf) => {
+              None => return None,
+              Some(aleaf) => {
                 if it.leaf_byte_pos >= aleaf.byte_len {
                     //We are actually past the end of the leaf
-                    it.leaf = option::None;
-                    return option::None
+                    it.leaf = None;
+                    return None
                 } else {
                     let range =
                         str::char_range_at(*aleaf.content,
@@ -1262,7 +1248,7 @@ pub mod node {
                     let ch = range.ch;
                     let next = range.next;
                     (*it).leaf_byte_pos = next - aleaf.byte_offset;
-                    return option::Some(ch)
+                    return Some(ch)
                 }
               }
             }
@@ -1273,11 +1259,7 @@ pub mod node {
 #[cfg(test)]
 mod tests {
     use rope::*;
-
-    use core::option;
-    use core::str;
-    use core::uint;
-    use core::vec;
+    use core::prelude::*;
 
     //Utility function, used for sanity check
     fn rope_to_string(r: Rope) -> ~str {
@@ -1341,11 +1323,11 @@ mod tests {
         let mut equal = true;
         while equal {
             match (node::char_iterator::next(&mut rope_iter)) {
-              option::None => {
+              None => {
                 if string_iter < string_len {
                     equal = false;
                 } break; }
-              option::Some(c) => {
+              Some(c) => {
                 let range = str::char_range_at(*sample, string_iter);
                 string_iter = range.next;
                 if range.ch != c { equal = false; break; }
@@ -1373,8 +1355,8 @@ mod tests {
         let mut it  = iterator::char::start(r);
         loop {
             match (node::char_iterator::next(&mut it)) {
-              option::None => break,
-              option::Some(_) => len += 1u
+              None => break,
+              Some(_) => len += 1u
             }
         }