surjective-enum

Rust macro to derive a surjective mapping from enum representation to enum.

Derive a surjective ::core::convert::From conversion function which maps all values which are not part of the enumeration to the last enum discriminant.

The example ``` rust use surjective_enum::From;

[repr(u8)]

[derive(From)]

pub enum Enum { Bar = 0b00, Foo = 0b01, Rest = 0b11 } ``` will create a from(u8) -> Enum conversion function which maps 0 -> Bar, 1 -> Foo and all other values to Rest.