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fp-ts

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Functional programming in TypeScript

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"use strict"; var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) { if (k2 === undefined) k2 = k; Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } }); }) : (function(o, m, k, k2) { if (k2 === undefined) k2 = k; o[k2] = m[k]; })); var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) { Object.defineProperty(o, "default", { enumerable: true, value: v }); }) : function(o, v) { o["default"] = v; }); var __importStar = (this && this.__importStar) || function (mod) { if (mod && mod.__esModule) return mod; var result = {}; if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k); __setModuleDefault(result, mod); return result; }; Object.defineProperty(exports, "__esModule", { value: true }); exports.getJoinMonoid = exports.getMeetMonoid = exports.getStructMonoid = exports.getEndomorphismMonoid = exports.getFunctionMonoid = exports.getDualMonoid = exports.getTupleMonoid = exports.fold = exports.monoidVoid = exports.monoidString = exports.monoidProduct = exports.monoidSum = exports.monoidAny = exports.monoidAll = void 0; var function_1 = require("./function"); var S = __importStar(require("./Semigroup")); /** * `boolean` monoid under conjunction. * * The `empty` value is `true`. * * @example * import * as M from 'fp-ts/Monoid' * * assert.deepStrictEqual(M.monoidAll.concat(true, true), true) * assert.deepStrictEqual(M.monoidAll.concat(true, false), false) * * @category instances * @since 2.0.0 */ exports.monoidAll = { concat: S.semigroupAll.concat, empty: true }; /** * `boolean` monoid under disjunction. * * The `empty` value is `false`. * * @example * import * as M from 'fp-ts/Monoid' * * assert.deepStrictEqual(M.monoidAny.concat(true, true), true) * assert.deepStrictEqual(M.monoidAny.concat(true, false), true) * assert.deepStrictEqual(M.monoidAny.concat(false, false), false) * * @category instances * @since 2.0.0 */ exports.monoidAny = { concat: S.semigroupAny.concat, empty: false }; /** * `number` monoid under addition. * * The `empty` value is `0`. * * @example * import * as M from 'fp-ts/Monoid' * * assert.deepStrictEqual(M.monoidSum.concat(2, 3), 5) * * @category instances * @since 2.0.0 */ exports.monoidSum = { concat: S.semigroupSum.concat, empty: 0 }; /** * `number` monoid under multiplication. * * The `empty` value is `1`. * * @example * import * as M from 'fp-ts/Monoid' * * assert.deepStrictEqual(M.monoidProduct.concat(2, 3), 6) * * @category instances * @since 2.0.0 */ exports.monoidProduct = { concat: S.semigroupProduct.concat, empty: 1 }; /** * `string` monoid under concatenation. * * The `empty` value is `''`. * * @example * import * as M from 'fp-ts/Monoid' * * assert.deepStrictEqual(M.monoidString.concat('a', 'b'), 'ab') * * @category instances * @since 2.0.0 */ exports.monoidString = { concat: S.semigroupString.concat, empty: '' }; /** * @category instances * @since 2.0.0 */ exports.monoidVoid = { concat: S.semigroupVoid.concat, empty: undefined }; /** * Given a sequence of `as`, concat them and return the total. * * If `as` is empty, return the monoid `empty` value. * * @example * import * as M from 'fp-ts/Monoid' * * assert.deepStrictEqual(M.fold(M.monoidSum)([1, 2, 3]), 6) * assert.deepStrictEqual(M.fold(M.monoidSum)([]), 0) * * @since 2.0.0 */ function fold(M) { return S.fold(M)(M.empty); } exports.fold = fold; /** * Given a tuple of monoids returns a monoid for the tuple * * @example * import { getTupleMonoid, monoidString, monoidSum, monoidAll } from 'fp-ts/Monoid' * * const M1 = getTupleMonoid(monoidString, monoidSum) * assert.deepStrictEqual(M1.concat(['a', 1], ['b', 2]), ['ab', 3]) * * const M2 = getTupleMonoid(monoidString, monoidSum, monoidAll) * assert.deepStrictEqual(M2.concat(['a', 1, true], ['b', 2, false]), ['ab', 3, false]) * * @category instances * @since 2.0.0 */ function getTupleMonoid() { var monoids = []; for (var _i = 0; _i < arguments.length; _i++) { monoids[_i] = arguments[_i]; } return { concat: S.getTupleSemigroup.apply(S, monoids).concat, empty: monoids.map(function (m) { return m.empty; }) }; } exports.getTupleMonoid = getTupleMonoid; /** * The dual of a `Monoid`, obtained by swapping the arguments of `concat`. * * @example * import { getDualMonoid, monoidString } from 'fp-ts/Monoid' * * assert.deepStrictEqual(getDualMonoid(monoidString).concat('a', 'b'), 'ba') * * @category combinators * @since 2.0.0 */ function getDualMonoid(M) { return { concat: S.getDualSemigroup(M).concat, empty: M.empty }; } exports.getDualMonoid = getDualMonoid; /** * Unary functions form a monoid as long as you can provide a monoid for the codomain. * * @example * import { Predicate } from 'fp-ts/function' * import * as M from 'fp-ts/Monoid' * * const f: Predicate<number> = (n) => n <= 2 * const g: Predicate<number> = (n) => n >= 0 * * const M1 = M.getFunctionMonoid(M.monoidAll)<number>() * * assert.deepStrictEqual(M1.concat(f, g)(1), true) * assert.deepStrictEqual(M1.concat(f, g)(3), false) * * const M2 = M.getFunctionMonoid(M.monoidAny)<number>() * * assert.deepStrictEqual(M2.concat(f, g)(1), true) * assert.deepStrictEqual(M2.concat(f, g)(3), true) * * @category instances * @since 2.0.0 */ function getFunctionMonoid(M) { return function () { return ({ concat: S.getFunctionSemigroup(M)().concat, empty: function () { return M.empty; } }); }; } exports.getFunctionMonoid = getFunctionMonoid; // TODO: swap execution order in v3 /** * Endomorphism form a monoid where the `empty` value is the identity function. * * @category instances * @since 2.0.0 */ function getEndomorphismMonoid() { return { concat: function (x, y) { return function (a) { return x(y(a)); }; }, empty: function_1.identity }; } exports.getEndomorphismMonoid = getEndomorphismMonoid; /** * Given a struct of monoids returns a monoid for the struct. * * @example * import * as M from 'fp-ts/Monoid' * * interface Point { * readonly x: number * readonly y: number * } * * const monoidPoint = M.getStructMonoid<Point>({ * x: M.monoidSum, * y: M.monoidSum * }) * * assert.deepStrictEqual(monoidPoint.concat({ x: 1, y: 2 }, { x: 3, y: 4 }), { x: 4, y: 6 }) * * @category instances * @since 2.0.0 */ function getStructMonoid(monoids) { var empty = {}; for (var _i = 0, _a = Object.keys(monoids); _i < _a.length; _i++) { var key = _a[_i]; empty[key] = monoids[key].empty; } return { concat: S.getStructSemigroup(monoids).concat, empty: empty }; } exports.getStructMonoid = getStructMonoid; /** * Get a monoid where `concat` will return the minimum, based on the provided bounded order. * * The `empty` value is the `top` value. * * @example * import * as B from 'fp-ts/Bounded' * import * as M from 'fp-ts/Monoid' * * const M1 = M.getMeetMonoid(B.boundedNumber) * * assert.deepStrictEqual(M1.concat(1, 2), 1) * * @category instances * @since 2.0.0 */ function getMeetMonoid(B) { return { concat: S.getMeetSemigroup(B).concat, empty: B.top }; } exports.getMeetMonoid = getMeetMonoid; /** * Get a monoid where `concat` will return the maximum, based on the provided bounded order. * * The `empty` value is the `bottom` value. * * @example * import * as B from 'fp-ts/Bounded' * import * as M from 'fp-ts/Monoid' * * const M1 = M.getJoinMonoid(B.boundedNumber) * * assert.deepStrictEqual(M1.concat(1, 2), 2) * * @category instances * @since 2.0.0 */ function getJoinMonoid(B) { return { concat: S.getJoinSemigroup(B).concat, empty: B.bottom }; } exports.getJoinMonoid = getJoinMonoid;