text: import AbortController, {AbortSignal} from './abortcontroller';
  import abortableFetch from './abortableFetch';
  
  (function(self) {
    'use strict';
  
    if (self.AbortController) {
      return;
    }
  
    self.AbortController = AbortController;
    self.AbortSignal = AbortSignal;
  
    if (!self.fetch) {
      console.warn('fetch() is not available, cannot install abortcontroller-polyfill');
      return;
    }
  
    const {fetch, Request} = abortableFetch(self);
    self.fetch = fetch;
    self.Request = Request;
  
  })(typeof self !== 'undefined' ? self : global);
  