pdfjs-dist/lib/shared/streams_polyfill.js

/**
 * @licstart The following is the entire license notice for the
 * Javascript code in this page
 *
 * Copyright 2017 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * @licend The above is the entire license notice for the
 * Javascript code in this page
 */
'use strict';

var isReadableStreamSupported = false;
if (typeof ReadableStream !== 'undefined') {
  try {
    new ReadableStream({
      start: function start(controller) {
        controller.close();
      }
    });
    isReadableStreamSupported = true;
  } catch (e) {}
}
if (isReadableStreamSupported) {
  exports.ReadableStream = ReadableStream;
} else {
  exports.ReadableStream = require('../../external/streams/streams-lib').ReadableStream;
}