36 lines
829 B
Rust
36 lines
829 B
Rust
use bad_optics::lenses::*;
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fn main() {
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let a = ((1, 2), 3);
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// use view to access inside the tuple
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let res = view(_0, a);
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assert_eq!(res, (1, 2));
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let res = view(_1, a);
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assert_eq!(res, 3);
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// you can combine lenses
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let lens = _0 + _1;
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// use the view function to access
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let res = view(lens, a);
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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);
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assert_eq!(res, 2);
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// call the over function to modify the value
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let a = over(lens, a, |v| v + 1);
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assert_eq!(a, ((1, 3), 3));
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// call the set function to set the value
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let a = set(lens, a, 5);
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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);
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assert_eq!(res, ((1, 6), 3));
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}
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