45 lines
1.4 KiB
JavaScript
45 lines
1.4 KiB
JavaScript
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/**
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* A `Functor` is a type constructor which supports a mapping operation `map`.
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*
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* `map` can be used to turn functions `a -> b` into functions `f a -> f b` whose argument and return types use the type
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* constructor `f` to represent some computational context.
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*
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* Instances must satisfy the following laws:
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*
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* 1. Identity: `F.map(fa, a => a) <-> fa`
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* 2. Composition: `F.map(fa, a => bc(ab(a))) <-> F.map(F.map(fa, ab), bc)`
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*
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* @since 2.0.0
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*/
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import { pipe } from './function';
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export function map(F, G) {
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return function (f) { return function (fa) { return F.map(fa, function (ga) { return G.map(ga, f); }); }; };
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}
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export function flap(F) {
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return function (a) { return function (fab) { return F.map(fab, function (f) { return f(a); }); }; };
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}
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export function bindTo(F) {
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return function (name) { return function (fa) { return F.map(fa, function (a) {
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var _a;
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return (_a = {}, _a[name] = a, _a);
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}); }; };
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}
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function let_(F) {
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return function (name, f) { return function (fa) { return F.map(fa, function (a) {
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var _a;
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return Object.assign({}, a, (_a = {}, _a[name] = f(a), _a));
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}); }; };
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}
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export {
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/**
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* @since 2.13.0
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*/
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let_ as let };
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/** @deprecated */
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export function getFunctorComposition(F, G) {
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var _map = map(F, G);
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return {
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map: function (fga, f) { return pipe(fga, _map(f)); }
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};
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}
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