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.find(predicate): Optic

ts
find: <A>(predicate: (a: A) => boolean) => PartialLens<A, A[]>;
ts
find: <A>(predicate: (a: A) => boolean) => PartialLens<A, A[]>;

This combinator takes a predicate and, when passed to derive, returns an optic focused on the first element in the focused array that matches the predicate.

ts
import { find } from "@optics/react/combinators";
 
const numbersOptic = createState([42, 16, 98, 123, 8, 245]);
 
const greaterThan100Optic = numbersOptic.derive(find((n) => n > 100));
              
const greaterThan100Optic: Optic<number, partial>
 
greaterThan100Optic.get(); // 123
 
greaterThan100Optic.set(99);
 
greaterThan100Optic.get(); // 245
ts
import { find } from "@optics/react/combinators";
 
const numbersOptic = createState([42, 16, 98, 123, 8, 245]);
 
const greaterThan100Optic = numbersOptic.derive(find((n) => n > 100));
              
const greaterThan100Optic: Optic<number, partial>
 
greaterThan100Optic.get(); // 123
 
greaterThan100Optic.set(99);
 
greaterThan100Optic.get(); // 245