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- 'use strict';
- var hasSymbols = typeof Symbol === 'function' && typeof Symbol.iterator === 'symbol';
- var isPrimitive = require('./helpers/isPrimitive');
- var isCallable = require('is-callable');
- var isDate = require('is-date-object');
- var isSymbol = require('is-symbol');
- var ordinaryToPrimitive = function OrdinaryToPrimitive(O, hint) {
- if (typeof O === 'undefined' || O === null) {
- throw new TypeError('Cannot call method on ' + O);
- }
- if (typeof hint !== 'string' || (hint !== 'number' && hint !== 'string')) {
- throw new TypeError('hint must be "string" or "number"');
- }
- var methodNames = hint === 'string' ? ['toString', 'valueOf'] : ['valueOf', 'toString'];
- var method, result, i;
- for (i = 0; i < methodNames.length; ++i) {
- method = O[methodNames[i]];
- if (isCallable(method)) {
- result = method.call(O);
- if (isPrimitive(result)) {
- return result;
- }
- }
- }
- throw new TypeError('No default value');
- };
- var GetMethod = function GetMethod(O, P) {
- var func = O[P];
- if (func !== null && typeof func !== 'undefined') {
- if (!isCallable(func)) {
- throw new TypeError(func + ' returned for property ' + P + ' of object ' + O + ' is not a function');
- }
- return func;
- }
- };
- // http://www.ecma-international.org/ecma-262/6.0/#sec-toprimitive
- module.exports = function ToPrimitive(input, PreferredType) {
- if (isPrimitive(input)) {
- return input;
- }
- var hint = 'default';
- if (arguments.length > 1) {
- if (PreferredType === String) {
- hint = 'string';
- } else if (PreferredType === Number) {
- hint = 'number';
- }
- }
- var exoticToPrim;
- if (hasSymbols) {
- if (Symbol.toPrimitive) {
- exoticToPrim = GetMethod(input, Symbol.toPrimitive);
- } else if (isSymbol(input)) {
- exoticToPrim = Symbol.prototype.valueOf;
- }
- }
- if (typeof exoticToPrim !== 'undefined') {
- var result = exoticToPrim.call(input, hint);
- if (isPrimitive(result)) {
- return result;
- }
- throw new TypeError('unable to convert exotic object to primitive');
- }
- if (hint === 'default' && (isDate(input) || isSymbol(input))) {
- hint = 'string';
- }
- return ordinaryToPrimitive(input, hint === 'default' ? 'number' : hint);
- };
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