Error code E0326

An implementation of a trait doesn't match the type constraint.

Erroneous code example:

#![allow(unused)]
fn main() {
trait Foo {
    const BAR: bool;
}

struct Bar;

impl Foo for Bar {
    const BAR: u32 = 5; // error, expected bool, found u32
}
}

The types of any associated constants in a trait implementation must match the types in the trait definition.