digenum

2 releases

0.1.1	Nov 19, 2022
0.1.0	Nov 19, 2022

#124 in #macros

MIT license

6KB
76 lines

An simple enum variant extractor

Can extract a (mutable) reference or turn into a tuple from fields. When variant is different than the expected, return None.

Example

use digenum::DigEnum;
use std::io::Read;

#[derive(DigEnum)]
enum Login<T: Read> {
    Local,
    Stream(T)
    Token([u8; 64]),
    UserAndPasswd(String, String),
}

Maps to:

Variant	Reference	Mutable Reference	Owned
`Local`	None	None	None
`Stream(T)`	`as_Stream -> Option<&T>`	`as_mut_Stream -> Option<&mut T>`	`into_Stream -> Option<T>`
`Token([u8; 64])`	`as_Token -> Option<&[u8; 64]>`	`as_mut_Token -> Option<&mut [u8; 64]>`	`into_Token -> Option<[u8; 64]>`
`UserAndPasswd(String, String)`	`as_UserAndPasswd -> Option<(&String, &String)>`	`as_mut_UserAndPasswd -> Option<(&mut String, &mut String)>`	`into_UserAndPasswd -> Option<(String, String)>`

"Why do not turn `snake_case`?"

Consider this example:

use digenum::DigEnum;

#[derive(DigEnum)]
enum Foo {
    FOO,
    foo,
    Foo
}

How should I handle it?

Works on

Empty enums
Empty variants
Single-fielded variants
Multiple-fielded variants
Different-case variants (like Foo::FOO and Foo::foo)
Generic variants
Unit variants
Struct-like variants

Dependencies

~1.5MB
~36K SLoC