Casts a value of type `S` to `T`. This is safe because the `Id` type is always guaranteed to only be inhabited by `Id<T, T>` types by construction.

Casts a value of type `&S` to `&T` where `S == T`. ```rust use refl::*; fn main() { let x: Box<u8> = Box::new(1); let refl: Id<Box<u8>, Box<u8>> = r

Casts a value of type `&S` to `&T` where `S == T`. ```rust use refl::*; fn main() { let mut x: Box<u8> = Box::new(1); let refl: Id<Box<u8>, Box<u8>>

Construct a proof witness of the fact that a type is equivalent to itself. This is equivalent to `Id::REFL`.

Converts `Id<S, T>` into `Id<T, S>` since type equality is symmetric.

If you have proofs `Id<S, T>` and `Id<T, U>` you can conclude `Id<S, U>` since type equality is transitive.