lodash/lodash.over/index.js

/**
 * lodash 4.3.0 (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');

/**
 * 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 {...*} 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;
}

/**
 * Creates a function like `_.over`.
 *
 * @private
 * @param {Function} arrayFunc The function to iterate over iteratees.
 * @returns {Function} Returns the new invoker function.
 */
function createOver(arrayFunc) {
  return rest(function(iteratees) {
    iteratees = arrayMap(baseFlatten(iteratees, 1), baseIteratee);
    return rest(function(args) {
      var thisArg = this;
      return arrayFunc(iteratees, function(iteratee) {
        return apply(iteratee, thisArg, args);
      });
    });
  });
}

/**
 * Creates a function that invokes `iteratees` with the arguments provided
 * to the created function and returns their results.
 *
 * @static
 * @memberOf _
 * @since 4.0.0
 * @category Util
 * @param {...(Function|Function[])} iteratees 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;