diff options
Diffstat (limited to 'src/libcore')
| -rw-r--r-- | src/libcore/cmp.rs | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/src/libcore/cmp.rs b/src/libcore/cmp.rs index b90c6daf9eb..a567eaa57d5 100644 --- a/src/libcore/cmp.rs +++ b/src/libcore/cmp.rs @@ -39,7 +39,7 @@ #![stable] -use option::{Option, Some}; +use option::{Option, Some, None}; /// Trait for values that can be compared for equality and inequality. /// @@ -268,6 +268,32 @@ pub fn max<T: Ord>(v1: T, v2: T) -> T { if v1 > v2 { v1 } else { v2 } } +/// Compare and return the minimum of two values if there is one. +/// +/// Returns the first argument if the comparison determines them to be equal. +#[inline] +#[experimental] +pub fn partial_min<T: PartialOrd>(v1: T, v2: T) -> Option<T> { + match v1.partial_cmp(&v2) { + Some(Less) | Some(Equal) => Some(v1), + Some(Greater) => Some(v2), + None => None + } +} + +/// Compare and return the maximum of two values if there is one. +/// +/// Returns the first argument if the comparison determines them to be equal. +#[inline] +#[experimental] +pub fn partial_max<T: PartialOrd>(v1: T, v2: T) -> Option<T> { + match v1.partial_cmp(&v2) { + Some(Less) => Some(v2), + Some(Equal) | Some(Greater) => Some(v1), + None => None + } +} + // Implementation of PartialEq, Eq, PartialOrd and Ord for primitive types mod impls { use cmp::{PartialOrd, Ord, PartialEq, Eq, Ordering, |