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@uirouter/core

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UI-Router Core: Framework agnostic, State-based routing for JavaScript Single Page Apps

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/** * Higher order functions * * These utility functions are exported, but are subject to change without notice. * * @packageDocumentation */ var __spreadArray = (this && this.__spreadArray) || function (to, from, pack) { if (pack || arguments.length === 2) for (var i = 0, l = from.length, ar; i < l; i++) { if (ar || !(i in from)) { if (!ar) ar = Array.prototype.slice.call(from, 0, i); ar[i] = from[i]; } } return to.concat(ar || Array.prototype.slice.call(from)); }; /** * Returns a new function for [Partial Application](https://en.wikipedia.org/wiki/Partial_application) of the original function. * * Given a function with N parameters, returns a new function that supports partial application. * The new function accepts anywhere from 1 to N parameters. When that function is called with M parameters, * where M is less than N, it returns a new function that accepts the remaining parameters. It continues to * accept more parameters until all N parameters have been supplied. * * * This contrived example uses a partially applied function as an predicate, which returns true * if an object is found in both arrays. * @example * ``` * // returns true if an object is in both of the two arrays * function inBoth(array1, array2, object) { * return array1.indexOf(object) !== -1 && * array2.indexOf(object) !== 1; * } * let obj1, obj2, obj3, obj4, obj5, obj6, obj7 * let foos = [obj1, obj3] * let bars = [obj3, obj4, obj5] * * // A curried "copy" of inBoth * let curriedInBoth = curry(inBoth); * // Partially apply both the array1 and array2 * let inFoosAndBars = curriedInBoth(foos, bars); * * // Supply the final argument; since all arguments are * // supplied, the original inBoth function is then called. * let obj1InBoth = inFoosAndBars(obj1); // false * * // Use the inFoosAndBars as a predicate. * // Filter, on each iteration, supplies the final argument * let allObjs = [ obj1, obj2, obj3, obj4, obj5, obj6, obj7 ]; * let foundInBoth = allObjs.filter(inFoosAndBars); // [ obj3 ] * * ``` * * @param fn * @returns {*|function(): (*|any)} */ export function curry(fn) { return function curried() { if (arguments.length >= fn.length) { return fn.apply(this, arguments); } var args = Array.prototype.slice.call(arguments); return curried.bind.apply(curried, __spreadArray([this], args, false)); }; } /** * Given a varargs list of functions, returns a function that composes the argument functions, right-to-left * given: f(x), g(x), h(x) * let composed = compose(f,g,h) * then, composed is: f(g(h(x))) */ export function compose() { var args = arguments; var start = args.length - 1; return function () { var i = start, result = args[start].apply(this, arguments); while (i--) result = args[i].call(this, result); return result; }; } /** * Given a varargs list of functions, returns a function that is composes the argument functions, left-to-right * given: f(x), g(x), h(x) * let piped = pipe(f,g,h); * then, piped is: h(g(f(x))) */ export function pipe() { var funcs = []; for (var _i = 0; _i < arguments.length; _i++) { funcs[_i] = arguments[_i]; } return compose.apply(null, [].slice.call(arguments).reverse()); } /** * Given a property name, returns a function that returns that property from an object * let obj = { foo: 1, name: "blarg" }; * let getName = prop("name"); * getName(obj) === "blarg" */ export var prop = function (name) { return function (obj) { return obj && obj[name]; }; }; /** * Given a property name and a value, returns a function that returns a boolean based on whether * the passed object has a property that matches the value * let obj = { foo: 1, name: "blarg" }; * let getName = propEq("name", "blarg"); * getName(obj) === true */ export var propEq = curry(function (name, _val, obj) { return obj && obj[name] === _val; }); /** * Given a dotted property name, returns a function that returns a nested property from an object, or undefined * let obj = { id: 1, nestedObj: { foo: 1, name: "blarg" }, }; * let getName = prop("nestedObj.name"); * getName(obj) === "blarg" * let propNotFound = prop("this.property.doesnt.exist"); * propNotFound(obj) === undefined */ export var parse = function (name) { return pipe.apply(null, name.split('.').map(prop)); }; /** * Given a function that returns a truthy or falsey value, returns a * function that returns the opposite (falsey or truthy) value given the same inputs */ export var not = function (fn) { return function () { var args = []; for (var _i = 0; _i < arguments.length; _i++) { args[_i] = arguments[_i]; } return !fn.apply(null, args); }; }; /** * Given two functions that return truthy or falsey values, returns a function that returns truthy * if both functions return truthy for the given arguments */ export function and(fn1, fn2) { return function () { var args = []; for (var _i = 0; _i < arguments.length; _i++) { args[_i] = arguments[_i]; } return fn1.apply(null, args) && fn2.apply(null, args); }; } /** * Given two functions that return truthy or falsey values, returns a function that returns truthy * if at least one of the functions returns truthy for the given arguments */ export function or(fn1, fn2) { return function () { var args = []; for (var _i = 0; _i < arguments.length; _i++) { args[_i] = arguments[_i]; } return fn1.apply(null, args) || fn2.apply(null, args); }; } /** * Check if all the elements of an array match a predicate function * * @param fn1 a predicate function `fn1` * @returns a function which takes an array and returns true if `fn1` is true for all elements of the array */ export var all = function (fn1) { return function (arr) { return arr.reduce(function (b, x) { return b && !!fn1(x); }, true); }; }; // tslint:disable-next-line:variable-name export var any = function (fn1) { return function (arr) { return arr.reduce(function (b, x) { return b || !!fn1(x); }, false); }; }; /** Given a class, returns a Predicate function that returns true if the object is of that class */ export var is = function (ctor) { return function (obj) { return (obj != null && obj.constructor === ctor) || obj instanceof ctor; }; }; /** Given a value, returns a Predicate function that returns true if another value is === equal to the original value */ export var eq = function (value) { return function (other) { return value === other; }; }; /** Given a value, returns a function which returns the value */ export var val = function (v) { return function () { return v; }; }; export function invoke(fnName, args) { return function (obj) { return obj[fnName].apply(obj, args); }; } /** * Sorta like Pattern Matching (a functional programming conditional construct) * * See http://c2.com/cgi/wiki?PatternMatching * * This is a conditional construct which allows a series of predicates and output functions * to be checked and then applied. Each predicate receives the input. If the predicate * returns truthy, then its matching output function (mapping function) is provided with * the input and, then the result is returned. * * Each combination (2-tuple) of predicate + output function should be placed in an array * of size 2: [ predicate, mapFn ] * * These 2-tuples should be put in an outer array. * * @example * ``` * * // Here's a 2-tuple where the first element is the isString predicate * // and the second element is a function that returns a description of the input * let firstTuple = [ angular.isString, (input) => `Heres your string ${input}` ]; * * // Second tuple: predicate "isNumber", mapfn returns a description * let secondTuple = [ angular.isNumber, (input) => `(${input}) That's a number!` ]; * * let third = [ (input) => input === null, (input) => `Oh, null...` ]; * * let fourth = [ (input) => input === undefined, (input) => `notdefined` ]; * * let descriptionOf = pattern([ firstTuple, secondTuple, third, fourth ]); * * console.log(descriptionOf(undefined)); // 'notdefined' * console.log(descriptionOf(55)); // '(55) That's a number!' * console.log(descriptionOf("foo")); // 'Here's your string foo' * ``` * * @param struct A 2D array. Each element of the array should be an array, a 2-tuple, * with a Predicate and a mapping/output function * @returns {function(any): *} */ export function pattern(struct) { return function (x) { for (var i = 0; i < struct.length; i++) { if (struct[i][0](x)) return struct[i][1](x); } }; } //# sourceMappingURL=hof.js.map