Struct type_eq::Constrain

pub struct Constrain;

A convenience struct for applying implementing TypeEq trait. Since the trait connects two types, this allows neither to be Self, and prevents issues with asymmetry.

Examples

use type_eq::{Constrain, TypeEq};
struct Example<A, B> { 
    // ... 
}
 
impl<A, B> Example<A, B> {
 
    // This method is only defined when A and B are the same type
    fn a_eq_b(&self) where Constrain: TypeEq<A, B> { }
 
    // This method is only defined when it's called with a parameter T which is
    // the same type as A
    fn a_eq_t<T>(&self, _t: T) where Constrain: TypeEq<A, T> { }
 
    // This method must be called with an explicit type. Since T is contrained to
    // be the same type as A and B, this can allow the caller a more convenient way of 
    // determining those types 
    fn infer_a<T>(&self) where Constrain: TypeEq<A, T> + TypeEq<B, T> { }
}

Trait Implementations

impl<A> TypeEq<A, A> for Constrain

fn as_eq(&self, a: A) -> A