const_fn
The tracking issue for this feature is: #57563
The const_fn
feature allows marking free functions and inherent methods as
const
, enabling them to be called in constants contexts, with constant
arguments.
Examples
#![feature(const_fn)] const fn double(x: i32) -> i32 { x * 2 } const FIVE: i32 = 5; const TEN: i32 = double(FIVE); fn main() { assert_eq!(5, FIVE); assert_eq!(10, TEN); }