1 unstable release
0.1.0 | Feb 23, 2022 |
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#24 in #companion
101 downloads per month
Used in 2 crates
5KB
86 lines
enum-tags
A Derive-Macro library that generates a companion tag-enum for any enum so that variants can be referred to without specifying fields.
Usage
Add this to your Cargo.toml:
[dependencies]
enum-tags = "0.1.0"
Then derive [Tag
] for any enum you want to generate a companion tag-enum for.
#[derive(Tag)]
enum MyEnum {
A,
B = 1024,
C(char),
D { x: i32, y: i32 },
}
The generated enum will look like this:
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
enum MyEnumTag {
A,
B = 1024,
C,
D,
}
An impl
for the TaggedEnum
trait will also be generated to allow conversion from your enum type to the tag-enum.
The generated impl
will look like this:
impl ::enum_tags_traits::TaggedEnum for MyEnum {
type Tag = MyEnumTag;
fn tag(&self) -> Self::Tag {
match *self {
Self::A => Self::Tag::A,
Self::B => Self::Tag::B,
Self::C(_) => Self::Tag::C,
Self::D { x: _, y: _ } => Self::Tag::D,
}
}
}
Dependencies
~1.5MB
~34K SLoC