bad-optics/README.md

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# bad optics
ergonomic no-macro lenses for rust
## example
```rust
use bad_optics::{
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lenses::{_0, _1},
*,
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};
fn main() {
let a = ((1, 2), 3);
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// 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
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let lens = _0 + _1;
// use the view function to access
let res = view(lens, a);
assert_eq!(res, 2);
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// you can also call the lens as a function
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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));
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// you can also call the lens as a function to modify the value
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let res = lens(a, |v| v + 1);
assert_eq!(res, ((1, 3), 3));
}
```