8 releases (stable)

1.2.2 Aug 29, 2023
1.2.1 Jun 1, 2022
1.1.0 May 30, 2022
0.1.0 May 29, 2022

#1681 in Rust patterns

23 downloads per month

MIT license

20KB
219 lines

Provides extension to rust enum

This crate provides Enumeration trait for rust enum with the following features

  • implementation for common traits (Clone, Copy, Hash, etc.)
  • getting number of variants through constant Enumeration::VARIANT_COUNT
  • casting between index (of type Enumeration::Index) and enumeration
  • attaching a constant value to each of the variants
  • runtime representation of enumeration
use enumeration::{prelude::*, OutOfRangeError};

enumerate!(pub Foo(u8; i32 = 11)
    Bar
    Baz = 99
);

pub fn main() -> Result<Foo, OutOfRangeError> {
    assert_eq!(Foo::Bar, Foo::variant(0)?);
    assert_eq!(Foo::Baz.to_index(), 1);
    assert_eq!(Foo::Bar.value(), 11);
    assert_eq!(Foo::Baz.value(), 99);
    
    let variants: Vec<Variant<_>> = vec![Foo::Bar.into(), SomeOtherExternalEnum::SomeVariant.into()];
    
    assert_eq!(variants[0].cast::<Foo>(), Ok(Foo::Bar));
    assert_eq!(variants[1].cast::<SomeOtherExternalEnum>(), Ok(SomeOtherExternalEnum::SomeVariant));
    assert!(variants[1].cast::<Foo>().is_err());
}

No runtime deps