Added Round trait to core

6 files changed, 126 insertions, 0 deletions

diff --git a/src/libcore/num/f32.rs b/src/libcore/num/f32.rs
index 795a9f9371c..43b68c5fc4f 100644
--- a/src/libcore/num/f32.rs
+++ b/src/libcore/num/f32.rs
@@ -306,6 +306,33 @@ pub extern {
     fn floorf32(val: f32) -> f32;
 }
 
+impl f32: num::Round {
+    #[inline(always)]
+    pure fn round(&self, mode: num::RoundMode) -> f32 {
+        match mode {
+            num::RoundDown                           => floor(*self),
+            num::RoundUp                             => ceil(*self),
+            num::RoundToZero   if is_negative(*self) => ceil(*self),
+            num::RoundToZero                         => floor(*self),
+            num::RoundFromZero if is_negative(*self) => floor(*self),
+            num::RoundFromZero                       => ceil(*self)
+        }
+    }
+
+    #[inline(always)]
+    pure fn floor(&self) -> f32 { floor(*self) }
+    #[inline(always)]
+    pure fn ceil(&self) -> f32 { ceil(*self) }
+    #[inline(always)]
+    pure fn fract(&self) -> f32 {
+        if is_negative(*self) {
+            (*self) - ceil(*self)
+        } else {
+            (*self) - floor(*self)
+        }
+    }
+}
+
 //
 // Local Variables:
 // mode: rust
diff --git a/src/libcore/num/f64.rs b/src/libcore/num/f64.rs
index 8cd94c9357d..851697012fc 100644
--- a/src/libcore/num/f64.rs
+++ b/src/libcore/num/f64.rs
@@ -330,6 +330,33 @@ pub extern {
     fn floorf64(val: f64) -> f64;
 }
 
+impl f64: num::Round {
+    #[inline(always)]
+    pure fn round(&self, mode: num::RoundMode) -> f64 {
+        match mode {
+            num::RoundDown                           => floor(*self),
+            num::RoundUp                             => ceil(*self),
+            num::RoundToZero   if is_negative(*self) => ceil(*self),
+            num::RoundToZero                         => floor(*self),
+            num::RoundFromZero if is_negative(*self) => floor(*self),
+            num::RoundFromZero                       => ceil(*self)
+        }
+    }
+
+    #[inline(always)]
+    pure fn floor(&self) -> f64 { floor(*self) }
+    #[inline(always)]
+    pure fn ceil(&self) -> f64 { ceil(*self) }
+    #[inline(always)]
+    pure fn fract(&self) -> f64 {
+        if is_negative(*self) {
+            (*self) - ceil(*self)
+        } else {
+            (*self) - floor(*self)
+        }
+    }
+}
+
 //
 // Local Variables:
 // mode: rust
diff --git a/src/libcore/num/float.rs b/src/libcore/num/float.rs
index b90edec4d96..1d1be6df87a 100644
--- a/src/libcore/num/float.rs
+++ b/src/libcore/num/float.rs
@@ -488,6 +488,39 @@ impl float: num::One {
     static pure fn one() -> float { 1.0 }
 }
 
+impl float: num::Round {
+    #[inline(always)]
+    pure fn round(&self, mode: num::RoundMode) -> float {
+        match mode {
+            num::RoundDown
+                => f64::floor(*self as f64) as float,
+            num::RoundUp
+                => f64::ceil(*self as f64) as float,
+            num::RoundToZero   if is_negative(*self)
+                => f64::ceil(*self as f64) as float,
+            num::RoundToZero
+                => f64::floor(*self as f64) as float,
+            num::RoundFromZero if is_negative(*self)
+                => f64::floor(*self as f64) as float,
+            num::RoundFromZero
+                => f64::ceil(*self as f64) as float
+        }
+    }
+
+    #[inline(always)]
+    pure fn floor(&self) -> float { f64::floor(*self as f64) as float}
+    #[inline(always)]
+    pure fn ceil(&self) -> float { f64::ceil(*self as f64) as float}
+    #[inline(always)]
+    pure fn fract(&self) -> float {
+        if is_negative(*self) {
+            (*self) - (f64::ceil(*self as f64) as float)
+        } else {
+            (*self) - (f64::floor(*self as f64) as float)
+        }
+    }
+}
+
 #[test]
 pub fn test_from_str() {
    assert from_str(~"3") == Some(3.);
diff --git a/src/libcore/num/int-template.rs b/src/libcore/num/int-template.rs
index 08508b09b70..7f3a15621ac 100644
--- a/src/libcore/num/int-template.rs
+++ b/src/libcore/num/int-template.rs
@@ -200,6 +200,18 @@ impl T: num::One {
     static pure fn one() -> T { 1 }
 }
 
+impl T: num::Round {
+    #[inline(always)]
+    pure fn round(&self, _: num::RoundMode) -> T { *self }
+
+    #[inline(always)]
+    pure fn floor(&self) -> T { *self }
+    #[inline(always)]
+    pure fn ceil(&self) -> T { *self }
+    #[inline(always)]
+    pure fn fract(&self) -> T { 0 }
+}
+
 /**
  * Parse a buffer of bytes
  *
diff --git a/src/libcore/num/num.rs b/src/libcore/num/num.rs
index 5680e3116bf..db8a741f185 100644
--- a/src/libcore/num/num.rs
+++ b/src/libcore/num/num.rs
@@ -35,3 +35,18 @@ pub trait Zero {
 pub trait One {
     static pure fn one() -> Self;
 }
+
+pub trait Round {
+    pure fn round(&self, mode: RoundMode) -> self;
+
+    pure fn floor(&self) -> self;
+    pure fn ceil(&self)  -> self;
+    pure fn fract(&self) -> self;
+}
+
+pub enum RoundMode {
+    RoundDown,
+    RoundUp,
+    RoundToZero,
+    RoundFromZero
+}
diff --git a/src/libcore/num/uint-template.rs b/src/libcore/num/uint-template.rs
index 1cd447df005..a59813b2df4 100644
--- a/src/libcore/num/uint-template.rs
+++ b/src/libcore/num/uint-template.rs
@@ -160,6 +160,18 @@ impl T: num::One {
     static pure fn one() -> T { 1 }
 }
 
+impl T: num::Round {
+    #[inline(always)]
+    pure fn round(&self, _: num::RoundMode) -> T { *self }
+
+    #[inline(always)]
+    pure fn floor(&self) -> T { *self }
+    #[inline(always)]
+    pure fn ceil(&self) -> T { *self }
+    #[inline(always)]
+    pure fn fract(&self) -> T { 0 }
+}
+
 /**
  * Parse a buffer of bytes
  *