36 lines
829 B
Rust
36 lines
829 B
Rust
use bad_optics::lenses::*;
|
|
|
|
fn main() {
|
|
let a = ((1, 2), 3);
|
|
|
|
// use view to access inside the tuple
|
|
let res = view(_0, a);
|
|
assert_eq!(res, (1, 2));
|
|
|
|
let res = view(_1, a);
|
|
assert_eq!(res, 3);
|
|
|
|
// you can combine lenses
|
|
let lens = _0 + _1;
|
|
|
|
// use the view function to access
|
|
let res = view(lens, a);
|
|
assert_eq!(res, 2);
|
|
|
|
// you can also call the lens as a function
|
|
let res = lens(a);
|
|
assert_eq!(res, 2);
|
|
|
|
// call the over function to modify the value
|
|
let a = over(lens, a, |v| v + 1);
|
|
assert_eq!(a, ((1, 3), 3));
|
|
|
|
// call the set function to set the value
|
|
let a = set(lens, a, 5);
|
|
assert_eq!(a, ((1, 5), 3));
|
|
|
|
// you can also call the lens as a function to modify the value
|
|
let res = lens(a, |v| v + 1);
|
|
assert_eq!(res, ((1, 3), 3));
|
|
}
|