File Content: sum.js var arraySum = require('../internal/arraySum'), baseCallback = require('../internal/baseCallback'), baseSum = require('../internal/baseSum'), isArray = require('../lang/isArray'), isIterateeCall = require('../internal/isIterateeCall'), toIterable = require('../internal/toIterable'); /** * Gets the sum of the values in `collection`. * * @static * @memberOf _ * @category Math * @param {Array|Object|string} collection The collection to iterate over. * @param {Function|Object|string} [iteratee] The function invoked per iteration. * @param {*} [thisArg] The `this` binding of `iteratee`. * @returns {number} Returns the sum. * @example * * _.sum([4, 6]); * // => 10 * * _.sum({ 'a': 4, 'b': 6 }); * // => 10 * * var objects = [ * { 'n': 4 }, * { 'n': 6 } * ]; * * _.sum(objects, function(object) { * return object.n; * }); * // => 10 * * // using the `_.property` callback shorthand * _.sum(objects, 'n'); * // => 10 */ function sum(collection, iteratee, thisArg) { if (thisArg && isIterateeCall(collection, iteratee, thisArg)) { iteratee = undefined; } iteratee = baseCallback(iteratee, thisArg, 3); return iteratee.length == 1 ? arraySum(isArray(collection) ? collection : toIterable(collection), iteratee) : baseSum(collection, iteratee); } module.exports = sum; Submit