type_val

This project allows for the creation of type-level values. Any value can be type-level as long as it can be initialized as a constant. All type-level values implement the TypeVal trait, and so can be provided as type parameters.

TypeVal

A trait implemented by type-level values. The value of a TypeVal can be extracted through the VAL associated constant.

def_type_val

This macro is used to implement the TypeVal trait. Any number of values can be initialized with a single invocation. Items prefixed by pub are public. Attributes to be applied to items in a block, including doc comments, should go above their targets.

Example

def_type_val! {
    type One: i32 = 1;
    #[derive(Clone, Copy)]
    type True: bool = true;
    /// Negative one
    pub type NegOne: i32 = -1;
    pub type False: bool = false;
}

println!("One = {}, True = {}, NegOne = {}, False = {}",
    One::VAL,
    True::VAL,
    NegOne::VAL,
    False::VAL);

How to Obtain

This project is available on crates.io here.