1 unstable release
Uses old Rust 2015
0.1.0 | Nov 24, 2018 |
---|
#8 in #macro-use
8KB
85 lines
e_num
Serialize enums into numbers.
Warning
This library works with variant fields (e.g. Variant1(u64)
) by bitshifting the
number representation of the contained value over enough so that the tagging can
fit on the right of the number. If you're dealing with very large numbers in the
fields or have a ton of variants, data on the left side of the value will likely
be lost.
Usage
#[macro_use]
extern crate e_num;
use e_num::ENum;
#[derive(ENum)]
enum A {
B,
C(u64),
}
fn main() {
let b: usize = A::B.to_num();
println!("b as a number: {:#b}", b);
let b = A::from_num(b);
assert!(match b {
A::B => true,
_ => false,
});
let c = A::C(85).to_num();
println!("c as a number: {:#b}", c);
let c = A::from_num(c);
assert!(match c {
A::C(inner) => {
assert_eq!(inner, 85);
true
}
_ => false,
});
}
License
This project is licensed under the MIT license. See the LICENSE file for more details.
lib.rs
:
E-Num(ber)
Serialize enums into numbers.
WARNING
This library works with variant fields (e.g. Variant1(u64)
) by
bitshifting the number representation of the contained value over
enough so that the tagging can fit on the right of the number. If
you're dealing with very large numbers in the fields or have a ton
of variants, data on the left side of the value will likely be lost.
Basic Usage
#[macro_use]
extern crate e_num;
use e_num::ENum;
#[derive(ENum)]
enum A {
B,
C(u64),
}
fn main() {
let b: usize = A::B.to_num();
println!("b as a number: {:#b}", b);
let b = A::from_num(b);
assert!(match b {
A::B => true,
_ => false,
});
let c = A::C(85).to_num();
println!("c as a number: {:#b}", c);
let c = A::from_num(c);
assert!(match c {
A::C(inner) => {
assert_eq!(inner, 85);
true
}
_ => false,
});
}
start_at
and constant variants
#[macro_use]
extern crate e_num;
use e_num::ENum;
#[derive(ENum)]
// where the non-constant variants will start counting from
#[e_num(start_at = 9)]
enum A {
// pulls the specified variant out from the rest of them
// and matches it against that number. constant variants
// can't have a field.
#[e_num(constant = 2)]
B,
C,
D,
E,
}
fn main() {
assert_eq!(A::B.to_num(), 2);
assert_eq!(A::C.to_num(), 9);
assert_eq!(A::D.to_num(), 10);
assert_eq!(A::E.to_num(), 11);
}
Dependencies
~2.5MB
~54K SLoC