lodash/lodash.add/index.js

/**
 * lodash 3.5.0 (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 baseToNumber = require('lodash._basetonumber'),
    baseToString = require('lodash._basetostring');

/**
 * Creates a function that performs a mathematical operation on two values.
 *
 * @private
 * @param {Function} operator The function to perform the operation.
 * @returns {Function} Returns the new mathematical operation function.
 */
function createMathOperation(operator) {
  return function(value, other) {
    var result;
    if (value === undefined && other === undefined) {
      return 0;
    }
    if (value !== undefined) {
      result = value;
    }
    if (other !== undefined) {
      if (result === undefined) {
        return other;
      }
      if (typeof value == 'string' || typeof other == 'string') {
        value = baseToString(value);
        other = baseToString(other);
      } else {
        value = baseToNumber(value);
        other = baseToNumber(other);
      }
      result = operator(value, other);
    }
    return result;
  };
}

/**
 * Adds two numbers.
 *
 * @static
 * @memberOf _
 * @since 3.4.0
 * @category Math
 * @param {number} augend The first number in an addition.
 * @param {number} addend The second number in an addition.
 * @returns {number} Returns the total.
 * @example
 *
 * _.add(6, 4);
 * // => 10
 */
var add = createMathOperation(function(augend, addend) {
  return augend + addend;
});

module.exports = add;