rust/src/libcore/cmp.rs

143 lines
3.3 KiB
Rust

/*!
The `Ord` and `Eq` comparison traits
This module contains the definition of both `Ord` and `Eq` which define
the common interfaces for doing comparison. Both are language items
that the compiler uses to implement the comparison operators. Rust code
may implement `Ord` to overload the `<`, `<=`, `>`, and `>=` operators,
and `Eq` to overload the `==` and `!=` operators.
*/
// NB: transitionary, de-mode-ing.
#[forbid(deprecated_mode)];
#[forbid(deprecated_pattern)];
pub use nounittest::*;
pub use unittest::*;
/// Interfaces used for comparison.
// Awful hack to work around duplicate lang items in core test.
#[cfg(notest)]
mod nounittest {
/**
* Trait for values that can be compared for a sort-order.
*
* Eventually this may be simplified to only require
* an `le` method, with the others generated from
* default implementations.
*/
#[lang="ord"]
#[cfg(stage0)]
pub trait Ord {
pure fn lt(other: &self) -> bool;
pure fn le(other: &self) -> bool;
pure fn ge(other: &self) -> bool;
pure fn gt(other: &self) -> bool;
}
#[lang="ord"]
#[cfg(stage1)]
#[cfg(stage2)]
pub trait Ord {
pure fn lt(&self, other: &self) -> bool;
pure fn le(&self, other: &self) -> bool;
pure fn ge(&self, other: &self) -> bool;
pure fn gt(&self, other: &self) -> bool;
}
#[lang="eq"]
/**
* Trait for values that can be compared for equality
* and inequality.
*
* Eventually this may be simplified to only require
* an `eq` method, with the other generated from
* a default implementation.
*/
#[lang="eq"]
#[cfg(stage0)]
pub trait Eq {
pure fn eq(other: &self) -> bool;
pure fn ne(other: &self) -> bool;
}
#[lang="eq"]
#[cfg(stage1)]
#[cfg(stage2)]
pub trait Eq {
pure fn eq(&self, other: &self) -> bool;
pure fn ne(&self, other: &self) -> bool;
}
}
#[cfg(test)]
mod nounittest {
#[legacy_exports];}
#[cfg(test)]
mod unittest {
#[legacy_exports];
#[cfg(stage0)]
pub trait Ord {
pure fn lt(other: &self) -> bool;
pure fn le(other: &self) -> bool;
pure fn ge(other: &self) -> bool;
pure fn gt(other: &self) -> bool;
}
#[cfg(stage1)]
#[cfg(stage2)]
pub trait Ord {
pure fn lt(&self, other: &self) -> bool;
pure fn le(&self, other: &self) -> bool;
pure fn ge(&self, other: &self) -> bool;
pure fn gt(&self, other: &self) -> bool;
}
#[cfg(stage0)]
pub trait Eq {
pure fn eq(other: &self) -> bool;
pure fn ne(other: &self) -> bool;
}
#[cfg(stage1)]
#[cfg(stage2)]
pub trait Eq {
pure fn eq(&self, other: &self) -> bool;
pure fn ne(&self, other: &self) -> bool;
}
}
#[cfg(notest)]
mod unittest {
#[legacy_exports];}
pub pure fn lt<T: Ord>(v1: &T, v2: &T) -> bool {
(*v1).lt(v2)
}
pub pure fn le<T: Ord Eq>(v1: &T, v2: &T) -> bool {
(*v1).lt(v2) || (*v1).eq(v2)
}
pub pure fn eq<T: Eq>(v1: &T, v2: &T) -> bool {
(*v1).eq(v2)
}
pub pure fn ne<T: Eq>(v1: &T, v2: &T) -> bool {
(*v1).ne(v2)
}
pub pure fn ge<T: Ord>(v1: &T, v2: &T) -> bool {
(*v1).ge(v2)
}
pub pure fn gt<T: Ord>(v1: &T, v2: &T) -> bool {
(*v1).gt(v2)
}