Macro typenum::op

macro_rules! op {
    ($($tail:tt)*) => { ... };
}

Convenient type operations.

Any types representing values must be able to be expressed as idents. That means they need to be in scope.

For example, P5 is okay, but typenum::P5 is not.

You may combine operators arbitrarily, although doing so excessively may require raising the recursion limit.

Example

#![recursion_limit="128"]
#[macro_use] extern crate typenum;
use typenum::consts::*;

fn main() {
    assert_type!(
        op!(min((P1 - P2) * (N3 + N7), P5 * (P3 + P4)) == P10)
    );
}

Operators are evaluated based on the operator precedence outlined here.

The full list of supported operators and functions is as follows:

*, /, %, +, -, <<, >>, &, ^, |, ==, !=, <=, >=, <, >, cmp, sqr, abs, cube, pow, min, max

They all expand to type aliases defined in the operator_aliases module. Here is an expanded list, including examples:

---

Operator *. Expands to Prod.

assert_type_eq!(op!(P2 * P3), P6);

---

Operator /. Expands to Quot.

assert_type_eq!(op!(P6 / P2), P3);

---

Operator %. Expands to Mod.

assert_type_eq!(op!(P5 % P3), P2);

---

Operator +. Expands to Sum.

assert_type_eq!(op!(P2 + P3), P5);

---

Operator -. Expands to Diff.

assert_type_eq!(op!(P2 - P3), N1);

---

Operator <<. Expands to Shleft.

assert_type_eq!(op!(U1 << U5), U32);

---

Operator >>. Expands to Shright.

assert_type_eq!(op!(U32 >> U5), U1);

---

Operator &. Expands to And.

assert_type_eq!(op!(U5 & U3), U1);

---

Operator ^. Expands to Xor.

assert_type_eq!(op!(U5 ^ U3), U6);

---

Operator |. Expands to Or.

assert_type_eq!(op!(U5 | U3), U7);

---

Operator ==. Expands to Eq.

assert_type_eq!(op!(P5 == P3 + P2), True);

---

Operator !=. Expands to NotEq.

assert_type_eq!(op!(P5 != P3 + P2), False);

---

Operator <=. Expands to LeEq.

assert_type_eq!(op!(P6 <= P3 + P2), False);

---

Operator >=. Expands to GrEq.

assert_type_eq!(op!(P6 >= P3 + P2), True);

---

Operator <. Expands to Le.

assert_type_eq!(op!(P4 < P3 + P2), True);

---

Operator >. Expands to Gr.

assert_type_eq!(op!(P5 < P3 + P2), False);

---

Operator cmp. Expands to Compare.

assert_type_eq!(op!(cmp(P2, P3)), Less);

---

Operator sqr. Expands to Square.

assert_type_eq!(op!(sqr(P2)), P4);

---

Operator abs. Expands to AbsVal.

assert_type_eq!(op!(abs(N2)), P2);

---

Operator cube. Expands to Cube.

assert_type_eq!(op!(cube(P2)), P8);

---

Operator pow. Expands to Exp.

assert_type_eq!(op!(pow(P2, P3)), P8);

---

Operator min. Expands to Minimum.

assert_type_eq!(op!(min(P2, P3)), P2);

---

Operator max. Expands to Maximum.

assert_type_eq!(op!(max(P2, P3)), P3);