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- /**
- * A `FunctorWithIndex` is a type constructor which supports a mapping operation `mapWithIndex`.
- *
- * `mapWithIndex` can be used to turn functions `i -> a -> b` into functions `f a -> f b` whose argument and return types use the type
- * constructor `f` to represent some computational context.
- *
- * Instances must satisfy the following laws:
- *
- * 1. Identity: `F.mapWithIndex(fa, (_i, a) => a) <-> fa`
- * 2. Composition: `F.mapWithIndex(fa, (_i, a) => bc(ab(a))) <-> F.mapWithIndex(F.mapWithIndex(fa, ab), bc)`
- *
- * @since 2.0.0
- */
- import { pipe } from './function';
- import { getFunctorComposition } from './Functor';
- export function mapWithIndex(F, G) {
- return function (f) { return function (fa) { return F.mapWithIndex(fa, function (i, ga) { return G.mapWithIndex(ga, function (j, a) { return f([i, j], a); }); }); }; };
- }
- /** @deprecated */
- export function getFunctorWithIndexComposition(F, G) {
- var map = getFunctorComposition(F, G).map;
- var _mapWithIndex = mapWithIndex(F, G);
- return {
- map: map,
- mapWithIndex: function (fga, f) { return pipe(fga, _mapWithIndex(f)); }
- };
- }
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