typenum

Macro cmp

source
macro_rules! cmp {
    ($a:ident < $b:ty) => { ... };
    ($a:ty, < $b:ty) => { ... };
    ($a:ident == $b:ty) => { ... };
    ($a:ty, == $b:ty) => { ... };
    ($a:ident > $b:ty) => { ... };
    ($a:ty, > $b:ty) => { ... };
    ($a:ident <= $b:ty) => { ... };
    ($a:ty, <= $b:ty) => { ... };
    ($a:ident != $b:ty) => { ... };
    ($a:ty, != $b:ty) => { ... };
    ($a:ident >= $b:ty) => { ... };
    ($a:ty, >= $b:ty) => { ... };
}
๐Ÿ‘ŽDeprecated since 1.9.0: use the op! macro instead
Expand description

A convenience macro for comparing type numbers. Use op! instead.

Due to the intricacies of the macro system, if the left-hand operand is more complex than a simple ident, you must place a comma between it and the comparison sign.

For example, you can do cmp!(P5 > P3) or cmp!(typenum::P5, > typenum::P3) but not cmp!(typenum::P5 > typenum::P3).

The result of this comparison will always be one of True (aka B1) or False (aka B0).

ยงExample

#[macro_use] extern crate typenum;
use typenum::consts::*;
use typenum::Bit;

fn main() {
type Result = cmp!(P9 == op!(P1 + P2 * (P2 - N2)));
assert_eq!(Result::to_bool(), true);
}