/*global self*/
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import Promise from './promise';
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export default function polyfill() {
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let local;
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if (typeof global !== 'undefined') {
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local = global;
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} else if (typeof self !== 'undefined') {
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local = self;
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} else {
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try {
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local = Function('return this')();
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} catch (e) {
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throw new Error('polyfill failed because global object is unavailable in this environment');
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}
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}
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let P = local.Promise;
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if (P) {
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var promiseToString = null;
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try {
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promiseToString = Object.prototype.toString.call(P.resolve());
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} catch(e) {
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// silently ignored
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}
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if (promiseToString === '[object Promise]' && !P.cast){
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return;
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}
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}
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local.Promise = Promise;
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}
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