tests/ui/transmutability/abstraction/const_generic_fn.rs

//@ check-pass
//! An array must have the correct length.

#![crate_type = "lib"]
#![feature(transmutability)]
#![allow(dead_code, incomplete_features, non_camel_case_types)]

mod assert {
    use std::mem::{Assume, TransmuteFrom};

    pub fn array_like<T, E, const N: usize>()
    where
        T: TransmuteFrom<[E; N], { Assume::SAFETY }>,
        [E; N]: TransmuteFrom<T, { Assume::SAFETY }>
    {}
}

fn len_0() {
    type Array = [u8; 0];
    #[repr(C)] struct Struct();
    assert::array_like::<Struct, u8, 0>();
}

fn len_1() {
    type Array = [u8; 1];
    #[repr(C)] struct Struct(u8);
    assert::array_like::<Struct, u8, 1>();
}

fn len_2() {
    type Array = [u8; 2];
    #[repr(C)] struct Struct(u8, u8);
    assert::array_like::<Struct, u8, 2>();
}

fn len_3() {
    type Array = [u8; 3];
    #[repr(C)] struct Struct(u8, u8, u8);
    assert::array_like::<Struct, u8, 3>();
}