lodash/lodash.over/index.js

/**
 * lodash (Custom Build) <https://lodash.com/>
 * Build: `lodash modularize exports="npm" -o ./`
 * Copyright jQuery Foundation and other contributors <https://jquery.org/>
 * Released under MIT license <https://lodash.com/license>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 */
var baseFlatten = require('lodash._baseflatten'),
    baseIteratee = require('lodash._baseiteratee'),
    rest = require('lodash.rest');

/** `Object#toString` result references. */
var funcTag = '[object Function]',
    genTag = '[object GeneratorFunction]';

/**
 * A faster alternative to `Function#apply`, this function invokes `func`
 * with the `this` binding of `thisArg` and the arguments of `args`.
 *
 * @private
 * @param {Function} func The function to invoke.
 * @param {*} thisArg The `this` binding of `func`.
 * @param {Array} args The arguments to invoke `func` with.
 * @returns {*} Returns the result of `func`.
 */
function apply(func, thisArg, args) {
  var length = args.length;
  switch (length) {
    case 0: return func.call(thisArg);
    case 1: return func.call(thisArg, args[0]);
    case 2: return func.call(thisArg, args[0], args[1]);
    case 3: return func.call(thisArg, args[0], args[1], args[2]);
  }
  return func.apply(thisArg, args);
}

/**
 * A specialized version of `_.map` for arrays without support for iteratee
 * shorthands.
 *
 * @private
 * @param {Array} array The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @returns {Array} Returns the new mapped array.
 */
function arrayMap(array, iteratee) {
  var index = -1,
      length = array.length,
      result = Array(length);

  while (++index < length) {
    result[index] = iteratee(array[index], index, array);
  }
  return result;
}

/**
 * The base implementation of `_.unary` without support for storing wrapper metadata.
 *
 * @private
 * @param {Function} func The function to cap arguments for.
 * @returns {Function} Returns the new capped function.
 */
function baseUnary(func) {
  return function(value) {
    return func(value);
  };
}

/** Used for built-in method references. */
var objectProto = Object.prototype;

/**
 * Used to resolve the
 * [`toStringTag`](http://ecma-international.org/ecma-262/6.0/#sec-object.prototype.tostring)
 * of values.
 */
var objectToString = objectProto.toString;

/**
 * Creates a function like `_.over`.
 *
 * @private
 * @param {Function} arrayFunc The function to iterate over iteratees.
 * @returns {Function} Returns the new over function.
 */
function createOver(arrayFunc) {
  return rest(function(iteratees) {
    iteratees = (iteratees.length == 1 && isArray(iteratees[0]))
      ? arrayMap(iteratees[0], baseUnary(baseIteratee))
      : arrayMap(baseFlatten(iteratees, 1, isFlattenableIteratee), baseUnary(baseIteratee));

    return rest(function(args) {
      var thisArg = this;
      return arrayFunc(iteratees, function(iteratee) {
        return apply(iteratee, thisArg, args);
      });
    });
  });
}

/**
 * Checks if `value` is a flattenable array and not a `_.matchesProperty`
 * iteratee shorthand.
 *
 * @private
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is flattenable, else `false`.
 */
function isFlattenableIteratee(value) {
  return isArray(value) && !(value.length == 2 && !isFunction(value[0]));
}

/**
 * Checks if `value` is classified as an `Array` object.
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @type {Function}
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is correctly classified,
 *  else `false`.
 * @example
 *
 * _.isArray([1, 2, 3]);
 * // => true
 *
 * _.isArray(document.body.children);
 * // => false
 *
 * _.isArray('abc');
 * // => false
 *
 * _.isArray(_.noop);
 * // => false
 */
var isArray = Array.isArray;

/**
 * Checks if `value` is classified as a `Function` object.
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is correctly classified,
 *  else `false`.
 * @example
 *
 * _.isFunction(_);
 * // => true
 *
 * _.isFunction(/abc/);
 * // => false
 */
function isFunction(value) {
  // The use of `Object#toString` avoids issues with the `typeof` operator
  // in Safari 8 which returns 'object' for typed array and weak map constructors,
  // and PhantomJS 1.9 which returns 'function' for `NodeList` instances.
  var tag = isObject(value) ? objectToString.call(value) : '';
  return tag == funcTag || tag == genTag;
}

/**
 * Checks if `value` is the
 * [language type](http://www.ecma-international.org/ecma-262/6.0/#sec-ecmascript-language-types)
 * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is an object, else `false`.
 * @example
 *
 * _.isObject({});
 * // => true
 *
 * _.isObject([1, 2, 3]);
 * // => true
 *
 * _.isObject(_.noop);
 * // => true
 *
 * _.isObject(null);
 * // => false
 */
function isObject(value) {
  var type = typeof value;
  return !!value && (type == 'object' || type == 'function');
}

/**
 * Creates a function that invokes `iteratees` with the arguments it receives
 * and returns their results.
 *
 * @static
 * @memberOf _
 * @since 4.0.0
 * @category Util
 * @param {...(Array|Array[]|Function|Function[]|Object|Object[]|string|string[])}
 *  [iteratees=[_.identity]] The iteratees to invoke.
 * @returns {Function} Returns the new function.
 * @example
 *
 * var func = _.over(Math.max, Math.min);
 *
 * func(1, 2, 3, 4);
 * // => [4, 1]
 */
var over = createOver(arrayMap);

module.exports = over;