enum-as-inner 0.2.1

A proc-macro for deriving inner field accessor functions on enums.
Documentation

enum-as-inner

A deriving proc-macro for generating functions to automatically give access to the inner members of enum.

Basic unnamed field case

The basic case is meant for single item enums, like:

#[macro_use]
extern crate enum_as_inner;

#[derive(EnumAsInner)]
enum OneEnum {
    One(u32),
}

where the inner item can be retrieved with the as_*() function:

let one = OneEnum::One(1);

assert_eq!(*one.as_one().unwrap(), 1);

the result is always a reference for inner items.

Unit case

This will return copy's of the value of the unit variant, as isize:

#[macro_use]
extern crate enum_as_inner;

#[derive(EnumAsInner)]
enum UnitVariants {
    Zero,
    One,
    Two,
}

These are not references:

let unit = UnitVariants::Two;

assert_eq!(unit.as_two().unwrap(), ());

Mutliple, unnamed field case

This will return a tuple of the inner types:

#[macro_use]
extern crate enum_as_inner;

#[derive(EnumAsInner)]
enum ManyVariants {
    One(u32),
    Two(u32, i32),
    Three(bool, u32, i64),
}

And can be accessed like:

let many = ManyVariants::Three(true, 1, 2);

assert_eq!(many.as_three().unwrap(), (&true, &1_u32, &2_i64));

Multiple, named field case

This will return a tuple of the inner types, like the unnamed option:

#[macro_use]
extern crate enum_as_inner;

#[derive(EnumAsInner)]
enum ManyVariants {
    One{ one: u32 },
    Two{ one: u32, two: i32 },
    Three{ one: bool, two: u32, three: i64 },
}

And can be accessed like:

let many = ManyVariants::Three{ one: true, two: 1, three: 2 };

assert_eq!(many.as_three().unwrap(), (&true, &1_u32, &2_i64));