typenum 1.3.0

Typenum is a Rust library for type-level numbers evaluated at compile time. It currently supports bits, unsigned integers, and signed integers.
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/*!
This crate provides type-level numbers evaluated at compile time. It depends only on libcore.

The traits defined or used in this crate are used in a typical manner. They can
be divided into two categories: **marker traits** and **type operators**.

Many of the marker traits have functions defined, but they all do essentially the same
thing: convert a type into its runtime counterpart, and are really just there for
debugging. For example,

```rust
use typenum::{N4, Integer};

assert_eq!(N4::to_i32(), -4);
```

**Type operators** are traits that behave as functions at the type level. These are the
meat of this library. Where possible, traits defined in libcore have been used, but
their attached functions have not been implemented.

For example, the `Add` trait is implemented for both unsigned and signed integers, but
the `add` function is not. As there are never any objects of the types defined here, it
wouldn't make sense to implement it. What is important is its associated type `Output`,
which is where the addition happens.

```rust
use std::ops::Add;
use typenum::{Integer, P3, P4};

type X = <P3 as Add<P4>>::Output;
assert_eq!(<X as Integer>::to_i32(), 7);
```

In addition, helper aliases are defined for type operators. For example, the above
snippet could be replaced with

```rust
use typenum::{Sum, Integer, P3, P4};

type X = Sum<P3, P4>;
assert_eq!(<X as Integer>::to_i32(), 7);
```

Documented in each module is the full list of type operators implemented.
 */
#![no_std]
#![warn(missing_docs)]

use core::cmp::Ordering;

macro_rules! impl_derivable {
    ($Type: ty) => (
        impl ::core::cmp::PartialEq for $Type {
            fn eq(&self, _: &Self) -> bool { match *self {} }
        }
        impl ::core::cmp::Eq for $Type { }
        impl ::core::cmp::PartialOrd for $Type {
            fn partial_cmp(&self, _: &Self) -> Option<::core::cmp::Ordering> { match *self {} }
        }
        impl ::core::cmp::Ord for $Type {
            fn cmp(&self, _: &Self) -> ::core::cmp::Ordering { match *self {} }
        }
        impl ::core::clone::Clone for $Type {
            fn clone(&self) -> Self { match *self {} }
        }
        impl ::core::marker::Copy for $Type {}
        impl ::core::hash::Hash for $Type {
            fn hash<H>(&self, _: &mut H) where H: ::core::hash::Hasher { match *self {} }
        }
        impl ::core::default::Default for $Type {
            fn default() -> Self { unreachable!() }
        }
        impl ::core::fmt::Debug for $Type {
            fn fmt(&self, _: &mut ::core::fmt::Formatter) -> ::core::result::Result<(), ::core::fmt::Error> {
                match *self {}
            }
        }
        );
}

pub mod consts;
pub mod bit;
pub mod uint;
pub mod int;
pub mod private;
pub mod marker_traits;
pub mod type_operators;
pub mod operator_aliases;

pub use consts::*;
pub use marker_traits::{NonZero, Ord, Bit, Unsigned, Integer};
pub use type_operators::{Cmp, Pow, Same};
pub use operator_aliases::{And, Or, Xor, Shleft, Shright, Sum, Diff, Prod, Quot, Mod, Negate, Exp, Add1, Sub1, Square, Cube, Compare};
pub use bit::{B0, B1};
pub use uint::{UInt, UTerm};
pub use int::{NInt, PInt};

/// A potential output from `Cmp`, this is the type equivalent to the enum variant
/// `core::cmp::Ordering::Greater`.
pub enum Greater {}
impl_derivable!{Greater}
/// A potential output from `Cmp`, this is the type equivalent to the enum variant
/// `core::cmp::Ordering::Less`.
pub enum Less {}
impl_derivable!{Less}
/// A potential output from `Cmp`, this is the type equivalent to the enum variant
/// `core::cmp::Ordering::Equal`.
pub enum Equal {}
impl_derivable!{Equal}

/// Returns `core::cmp::Ordering::Greater`
impl Ord for Greater {
    #[inline]
    fn to_ordering() -> Ordering {
        Ordering::Greater
    }
}
/// Returns `core::cmp::Ordering::Less`
impl Ord for Less {
    #[inline]
    fn to_ordering() -> Ordering {
        Ordering::Less
    }
}
/// Returns `core::cmp::Ordering::Equal`
impl Ord for Equal {
    #[inline]
    fn to_ordering() -> Ordering {
        Ordering::Equal
    }
}