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							635 lines
						
					
					
						
							17 KiB
						
					
					
				/**
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 * @license React
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 * scheduler.development.js
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 *
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 * Copyright (c) Facebook, Inc. and its affiliates.
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 *
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 * This source code is licensed under the MIT license found in the
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 * LICENSE file in the root directory of this source tree.
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 */
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'use strict';
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if (process.env.NODE_ENV !== "production") {
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  (function() {
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          'use strict';
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/* global __REACT_DEVTOOLS_GLOBAL_HOOK__ */
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if (
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  typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ !== 'undefined' &&
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  typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStart ===
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    'function'
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) {
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  __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStart(new Error());
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}
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          var enableSchedulerDebugging = false;
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var enableProfiling = false;
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var frameYieldMs = 5;
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function push(heap, node) {
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  var index = heap.length;
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  heap.push(node);
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  siftUp(heap, node, index);
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}
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function peek(heap) {
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  return heap.length === 0 ? null : heap[0];
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}
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function pop(heap) {
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  if (heap.length === 0) {
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    return null;
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  }
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  var first = heap[0];
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  var last = heap.pop();
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  if (last !== first) {
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    heap[0] = last;
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    siftDown(heap, last, 0);
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  }
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  return first;
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}
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function siftUp(heap, node, i) {
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  var index = i;
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  while (index > 0) {
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    var parentIndex = index - 1 >>> 1;
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    var parent = heap[parentIndex];
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    if (compare(parent, node) > 0) {
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      // The parent is larger. Swap positions.
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      heap[parentIndex] = node;
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      heap[index] = parent;
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      index = parentIndex;
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    } else {
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      // The parent is smaller. Exit.
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      return;
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    }
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  }
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}
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function siftDown(heap, node, i) {
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  var index = i;
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  var length = heap.length;
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  var halfLength = length >>> 1;
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  while (index < halfLength) {
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    var leftIndex = (index + 1) * 2 - 1;
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    var left = heap[leftIndex];
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    var rightIndex = leftIndex + 1;
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    var right = heap[rightIndex]; // If the left or right node is smaller, swap with the smaller of those.
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    if (compare(left, node) < 0) {
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      if (rightIndex < length && compare(right, left) < 0) {
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        heap[index] = right;
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        heap[rightIndex] = node;
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        index = rightIndex;
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      } else {
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        heap[index] = left;
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        heap[leftIndex] = node;
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        index = leftIndex;
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      }
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    } else if (rightIndex < length && compare(right, node) < 0) {
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      heap[index] = right;
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      heap[rightIndex] = node;
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      index = rightIndex;
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    } else {
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      // Neither child is smaller. Exit.
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      return;
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    }
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  }
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}
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function compare(a, b) {
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  // Compare sort index first, then task id.
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  var diff = a.sortIndex - b.sortIndex;
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  return diff !== 0 ? diff : a.id - b.id;
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}
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// TODO: Use symbols?
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var ImmediatePriority = 1;
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var UserBlockingPriority = 2;
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var NormalPriority = 3;
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var LowPriority = 4;
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var IdlePriority = 5;
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function markTaskErrored(task, ms) {
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}
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/* eslint-disable no-var */
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var hasPerformanceNow = typeof performance === 'object' && typeof performance.now === 'function';
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if (hasPerformanceNow) {
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  var localPerformance = performance;
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  exports.unstable_now = function () {
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    return localPerformance.now();
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  };
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} else {
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  var localDate = Date;
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  var initialTime = localDate.now();
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  exports.unstable_now = function () {
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    return localDate.now() - initialTime;
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  };
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} // Max 31 bit integer. The max integer size in V8 for 32-bit systems.
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// Math.pow(2, 30) - 1
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// 0b111111111111111111111111111111
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var maxSigned31BitInt = 1073741823; // Times out immediately
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var IMMEDIATE_PRIORITY_TIMEOUT = -1; // Eventually times out
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var USER_BLOCKING_PRIORITY_TIMEOUT = 250;
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var NORMAL_PRIORITY_TIMEOUT = 5000;
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var LOW_PRIORITY_TIMEOUT = 10000; // Never times out
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var IDLE_PRIORITY_TIMEOUT = maxSigned31BitInt; // Tasks are stored on a min heap
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var taskQueue = [];
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var timerQueue = []; // Incrementing id counter. Used to maintain insertion order.
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var taskIdCounter = 1; // Pausing the scheduler is useful for debugging.
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var currentTask = null;
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var currentPriorityLevel = NormalPriority; // This is set while performing work, to prevent re-entrance.
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var isPerformingWork = false;
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var isHostCallbackScheduled = false;
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var isHostTimeoutScheduled = false; // Capture local references to native APIs, in case a polyfill overrides them.
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var localSetTimeout = typeof setTimeout === 'function' ? setTimeout : null;
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var localClearTimeout = typeof clearTimeout === 'function' ? clearTimeout : null;
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var localSetImmediate = typeof setImmediate !== 'undefined' ? setImmediate : null; // IE and Node.js + jsdom
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var isInputPending = typeof navigator !== 'undefined' && navigator.scheduling !== undefined && navigator.scheduling.isInputPending !== undefined ? navigator.scheduling.isInputPending.bind(navigator.scheduling) : null;
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function advanceTimers(currentTime) {
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  // Check for tasks that are no longer delayed and add them to the queue.
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  var timer = peek(timerQueue);
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  while (timer !== null) {
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    if (timer.callback === null) {
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      // Timer was cancelled.
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      pop(timerQueue);
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    } else if (timer.startTime <= currentTime) {
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      // Timer fired. Transfer to the task queue.
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      pop(timerQueue);
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      timer.sortIndex = timer.expirationTime;
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      push(taskQueue, timer);
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    } else {
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      // Remaining timers are pending.
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      return;
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    }
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    timer = peek(timerQueue);
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  }
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}
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function handleTimeout(currentTime) {
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  isHostTimeoutScheduled = false;
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  advanceTimers(currentTime);
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  if (!isHostCallbackScheduled) {
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    if (peek(taskQueue) !== null) {
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      isHostCallbackScheduled = true;
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      requestHostCallback(flushWork);
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    } else {
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      var firstTimer = peek(timerQueue);
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      if (firstTimer !== null) {
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        requestHostTimeout(handleTimeout, firstTimer.startTime - currentTime);
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      }
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    }
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  }
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}
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function flushWork(hasTimeRemaining, initialTime) {
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  isHostCallbackScheduled = false;
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  if (isHostTimeoutScheduled) {
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    // We scheduled a timeout but it's no longer needed. Cancel it.
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    isHostTimeoutScheduled = false;
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    cancelHostTimeout();
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  }
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  isPerformingWork = true;
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  var previousPriorityLevel = currentPriorityLevel;
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  try {
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    if (enableProfiling) {
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      try {
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        return workLoop(hasTimeRemaining, initialTime);
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      } catch (error) {
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        if (currentTask !== null) {
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          var currentTime = exports.unstable_now();
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          markTaskErrored(currentTask, currentTime);
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          currentTask.isQueued = false;
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        }
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        throw error;
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      }
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    } else {
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      // No catch in prod code path.
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      return workLoop(hasTimeRemaining, initialTime);
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    }
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  } finally {
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    currentTask = null;
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    currentPriorityLevel = previousPriorityLevel;
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    isPerformingWork = false;
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  }
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}
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function workLoop(hasTimeRemaining, initialTime) {
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  var currentTime = initialTime;
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  advanceTimers(currentTime);
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  currentTask = peek(taskQueue);
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  while (currentTask !== null && !(enableSchedulerDebugging )) {
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    if (currentTask.expirationTime > currentTime && (!hasTimeRemaining || shouldYieldToHost())) {
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      // This currentTask hasn't expired, and we've reached the deadline.
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      break;
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    }
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    var callback = currentTask.callback;
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    if (typeof callback === 'function') {
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      currentTask.callback = null;
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      currentPriorityLevel = currentTask.priorityLevel;
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      var didUserCallbackTimeout = currentTask.expirationTime <= currentTime;
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      var continuationCallback = callback(didUserCallbackTimeout);
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      currentTime = exports.unstable_now();
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      if (typeof continuationCallback === 'function') {
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        currentTask.callback = continuationCallback;
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      } else {
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        if (currentTask === peek(taskQueue)) {
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          pop(taskQueue);
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        }
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      }
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      advanceTimers(currentTime);
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    } else {
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      pop(taskQueue);
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    }
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    currentTask = peek(taskQueue);
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  } // Return whether there's additional work
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  if (currentTask !== null) {
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    return true;
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  } else {
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    var firstTimer = peek(timerQueue);
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    if (firstTimer !== null) {
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      requestHostTimeout(handleTimeout, firstTimer.startTime - currentTime);
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    }
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    return false;
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  }
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}
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function unstable_runWithPriority(priorityLevel, eventHandler) {
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  switch (priorityLevel) {
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    case ImmediatePriority:
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    case UserBlockingPriority:
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    case NormalPriority:
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    case LowPriority:
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    case IdlePriority:
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      break;
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    default:
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      priorityLevel = NormalPriority;
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  }
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  var previousPriorityLevel = currentPriorityLevel;
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  currentPriorityLevel = priorityLevel;
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  try {
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    return eventHandler();
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  } finally {
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    currentPriorityLevel = previousPriorityLevel;
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  }
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}
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function unstable_next(eventHandler) {
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  var priorityLevel;
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  switch (currentPriorityLevel) {
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    case ImmediatePriority:
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    case UserBlockingPriority:
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    case NormalPriority:
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      // Shift down to normal priority
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      priorityLevel = NormalPriority;
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      break;
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    default:
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      // Anything lower than normal priority should remain at the current level.
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      priorityLevel = currentPriorityLevel;
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      break;
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  }
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  var previousPriorityLevel = currentPriorityLevel;
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  currentPriorityLevel = priorityLevel;
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  try {
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    return eventHandler();
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  } finally {
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    currentPriorityLevel = previousPriorityLevel;
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  }
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}
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function unstable_wrapCallback(callback) {
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  var parentPriorityLevel = currentPriorityLevel;
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  return function () {
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    // This is a fork of runWithPriority, inlined for performance.
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    var previousPriorityLevel = currentPriorityLevel;
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    currentPriorityLevel = parentPriorityLevel;
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    try {
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      return callback.apply(this, arguments);
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    } finally {
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      currentPriorityLevel = previousPriorityLevel;
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    }
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  };
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}
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function unstable_scheduleCallback(priorityLevel, callback, options) {
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  var currentTime = exports.unstable_now();
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  var startTime;
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						|
  if (typeof options === 'object' && options !== null) {
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    var delay = options.delay;
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    if (typeof delay === 'number' && delay > 0) {
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      startTime = currentTime + delay;
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    } else {
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      startTime = currentTime;
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    }
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  } else {
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    startTime = currentTime;
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  }
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  var timeout;
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 | 
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  switch (priorityLevel) {
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    case ImmediatePriority:
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      timeout = IMMEDIATE_PRIORITY_TIMEOUT;
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      break;
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 | 
						|
    case UserBlockingPriority:
 | 
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      timeout = USER_BLOCKING_PRIORITY_TIMEOUT;
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						|
      break;
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						|
 | 
						|
    case IdlePriority:
 | 
						|
      timeout = IDLE_PRIORITY_TIMEOUT;
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						|
      break;
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						|
 | 
						|
    case LowPriority:
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      timeout = LOW_PRIORITY_TIMEOUT;
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						|
      break;
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						|
 | 
						|
    case NormalPriority:
 | 
						|
    default:
 | 
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      timeout = NORMAL_PRIORITY_TIMEOUT;
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						|
      break;
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						|
  }
 | 
						|
 | 
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  var expirationTime = startTime + timeout;
 | 
						|
  var newTask = {
 | 
						|
    id: taskIdCounter++,
 | 
						|
    callback: callback,
 | 
						|
    priorityLevel: priorityLevel,
 | 
						|
    startTime: startTime,
 | 
						|
    expirationTime: expirationTime,
 | 
						|
    sortIndex: -1
 | 
						|
  };
 | 
						|
 | 
						|
  if (startTime > currentTime) {
 | 
						|
    // This is a delayed task.
 | 
						|
    newTask.sortIndex = startTime;
 | 
						|
    push(timerQueue, newTask);
 | 
						|
 | 
						|
    if (peek(taskQueue) === null && newTask === peek(timerQueue)) {
 | 
						|
      // All tasks are delayed, and this is the task with the earliest delay.
 | 
						|
      if (isHostTimeoutScheduled) {
 | 
						|
        // Cancel an existing timeout.
 | 
						|
        cancelHostTimeout();
 | 
						|
      } else {
 | 
						|
        isHostTimeoutScheduled = true;
 | 
						|
      } // Schedule a timeout.
 | 
						|
 | 
						|
 | 
						|
      requestHostTimeout(handleTimeout, startTime - currentTime);
 | 
						|
    }
 | 
						|
  } else {
 | 
						|
    newTask.sortIndex = expirationTime;
 | 
						|
    push(taskQueue, newTask);
 | 
						|
    // wait until the next time we yield.
 | 
						|
 | 
						|
 | 
						|
    if (!isHostCallbackScheduled && !isPerformingWork) {
 | 
						|
      isHostCallbackScheduled = true;
 | 
						|
      requestHostCallback(flushWork);
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
  return newTask;
 | 
						|
}
 | 
						|
 | 
						|
function unstable_pauseExecution() {
 | 
						|
}
 | 
						|
 | 
						|
function unstable_continueExecution() {
 | 
						|
 | 
						|
  if (!isHostCallbackScheduled && !isPerformingWork) {
 | 
						|
    isHostCallbackScheduled = true;
 | 
						|
    requestHostCallback(flushWork);
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
function unstable_getFirstCallbackNode() {
 | 
						|
  return peek(taskQueue);
 | 
						|
}
 | 
						|
 | 
						|
function unstable_cancelCallback(task) {
 | 
						|
  // remove from the queue because you can't remove arbitrary nodes from an
 | 
						|
  // array based heap, only the first one.)
 | 
						|
 | 
						|
 | 
						|
  task.callback = null;
 | 
						|
}
 | 
						|
 | 
						|
function unstable_getCurrentPriorityLevel() {
 | 
						|
  return currentPriorityLevel;
 | 
						|
}
 | 
						|
 | 
						|
var isMessageLoopRunning = false;
 | 
						|
var scheduledHostCallback = null;
 | 
						|
var taskTimeoutID = -1; // Scheduler periodically yields in case there is other work on the main
 | 
						|
// thread, like user events. By default, it yields multiple times per frame.
 | 
						|
// It does not attempt to align with frame boundaries, since most tasks don't
 | 
						|
// need to be frame aligned; for those that do, use requestAnimationFrame.
 | 
						|
 | 
						|
var frameInterval = frameYieldMs;
 | 
						|
var startTime = -1;
 | 
						|
 | 
						|
function shouldYieldToHost() {
 | 
						|
  var timeElapsed = exports.unstable_now() - startTime;
 | 
						|
 | 
						|
  if (timeElapsed < frameInterval) {
 | 
						|
    // The main thread has only been blocked for a really short amount of time;
 | 
						|
    // smaller than a single frame. Don't yield yet.
 | 
						|
    return false;
 | 
						|
  } // The main thread has been blocked for a non-negligible amount of time. We
 | 
						|
 | 
						|
 | 
						|
  return true;
 | 
						|
}
 | 
						|
 | 
						|
function requestPaint() {
 | 
						|
 | 
						|
}
 | 
						|
 | 
						|
function forceFrameRate(fps) {
 | 
						|
  if (fps < 0 || fps > 125) {
 | 
						|
    // Using console['error'] to evade Babel and ESLint
 | 
						|
    console['error']('forceFrameRate takes a positive int between 0 and 125, ' + 'forcing frame rates higher than 125 fps is not supported');
 | 
						|
    return;
 | 
						|
  }
 | 
						|
 | 
						|
  if (fps > 0) {
 | 
						|
    frameInterval = Math.floor(1000 / fps);
 | 
						|
  } else {
 | 
						|
    // reset the framerate
 | 
						|
    frameInterval = frameYieldMs;
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
var performWorkUntilDeadline = function () {
 | 
						|
  if (scheduledHostCallback !== null) {
 | 
						|
    var currentTime = exports.unstable_now(); // Keep track of the start time so we can measure how long the main thread
 | 
						|
    // has been blocked.
 | 
						|
 | 
						|
    startTime = currentTime;
 | 
						|
    var hasTimeRemaining = true; // If a scheduler task throws, exit the current browser task so the
 | 
						|
    // error can be observed.
 | 
						|
    //
 | 
						|
    // Intentionally not using a try-catch, since that makes some debugging
 | 
						|
    // techniques harder. Instead, if `scheduledHostCallback` errors, then
 | 
						|
    // `hasMoreWork` will remain true, and we'll continue the work loop.
 | 
						|
 | 
						|
    var hasMoreWork = true;
 | 
						|
 | 
						|
    try {
 | 
						|
      hasMoreWork = scheduledHostCallback(hasTimeRemaining, currentTime);
 | 
						|
    } finally {
 | 
						|
      if (hasMoreWork) {
 | 
						|
        // If there's more work, schedule the next message event at the end
 | 
						|
        // of the preceding one.
 | 
						|
        schedulePerformWorkUntilDeadline();
 | 
						|
      } else {
 | 
						|
        isMessageLoopRunning = false;
 | 
						|
        scheduledHostCallback = null;
 | 
						|
      }
 | 
						|
    }
 | 
						|
  } else {
 | 
						|
    isMessageLoopRunning = false;
 | 
						|
  } // Yielding to the browser will give it a chance to paint, so we can
 | 
						|
};
 | 
						|
 | 
						|
var schedulePerformWorkUntilDeadline;
 | 
						|
 | 
						|
if (typeof localSetImmediate === 'function') {
 | 
						|
  // Node.js and old IE.
 | 
						|
  // There's a few reasons for why we prefer setImmediate.
 | 
						|
  //
 | 
						|
  // Unlike MessageChannel, it doesn't prevent a Node.js process from exiting.
 | 
						|
  // (Even though this is a DOM fork of the Scheduler, you could get here
 | 
						|
  // with a mix of Node.js 15+, which has a MessageChannel, and jsdom.)
 | 
						|
  // https://github.com/facebook/react/issues/20756
 | 
						|
  //
 | 
						|
  // But also, it runs earlier which is the semantic we want.
 | 
						|
  // If other browsers ever implement it, it's better to use it.
 | 
						|
  // Although both of these would be inferior to native scheduling.
 | 
						|
  schedulePerformWorkUntilDeadline = function () {
 | 
						|
    localSetImmediate(performWorkUntilDeadline);
 | 
						|
  };
 | 
						|
} else if (typeof MessageChannel !== 'undefined') {
 | 
						|
  // DOM and Worker environments.
 | 
						|
  // We prefer MessageChannel because of the 4ms setTimeout clamping.
 | 
						|
  var channel = new MessageChannel();
 | 
						|
  var port = channel.port2;
 | 
						|
  channel.port1.onmessage = performWorkUntilDeadline;
 | 
						|
 | 
						|
  schedulePerformWorkUntilDeadline = function () {
 | 
						|
    port.postMessage(null);
 | 
						|
  };
 | 
						|
} else {
 | 
						|
  // We should only fallback here in non-browser environments.
 | 
						|
  schedulePerformWorkUntilDeadline = function () {
 | 
						|
    localSetTimeout(performWorkUntilDeadline, 0);
 | 
						|
  };
 | 
						|
}
 | 
						|
 | 
						|
function requestHostCallback(callback) {
 | 
						|
  scheduledHostCallback = callback;
 | 
						|
 | 
						|
  if (!isMessageLoopRunning) {
 | 
						|
    isMessageLoopRunning = true;
 | 
						|
    schedulePerformWorkUntilDeadline();
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
function requestHostTimeout(callback, ms) {
 | 
						|
  taskTimeoutID = localSetTimeout(function () {
 | 
						|
    callback(exports.unstable_now());
 | 
						|
  }, ms);
 | 
						|
}
 | 
						|
 | 
						|
function cancelHostTimeout() {
 | 
						|
  localClearTimeout(taskTimeoutID);
 | 
						|
  taskTimeoutID = -1;
 | 
						|
}
 | 
						|
 | 
						|
var unstable_requestPaint = requestPaint;
 | 
						|
var unstable_Profiling =  null;
 | 
						|
 | 
						|
exports.unstable_IdlePriority = IdlePriority;
 | 
						|
exports.unstable_ImmediatePriority = ImmediatePriority;
 | 
						|
exports.unstable_LowPriority = LowPriority;
 | 
						|
exports.unstable_NormalPriority = NormalPriority;
 | 
						|
exports.unstable_Profiling = unstable_Profiling;
 | 
						|
exports.unstable_UserBlockingPriority = UserBlockingPriority;
 | 
						|
exports.unstable_cancelCallback = unstable_cancelCallback;
 | 
						|
exports.unstable_continueExecution = unstable_continueExecution;
 | 
						|
exports.unstable_forceFrameRate = forceFrameRate;
 | 
						|
exports.unstable_getCurrentPriorityLevel = unstable_getCurrentPriorityLevel;
 | 
						|
exports.unstable_getFirstCallbackNode = unstable_getFirstCallbackNode;
 | 
						|
exports.unstable_next = unstable_next;
 | 
						|
exports.unstable_pauseExecution = unstable_pauseExecution;
 | 
						|
exports.unstable_requestPaint = unstable_requestPaint;
 | 
						|
exports.unstable_runWithPriority = unstable_runWithPriority;
 | 
						|
exports.unstable_scheduleCallback = unstable_scheduleCallback;
 | 
						|
exports.unstable_shouldYield = shouldYieldToHost;
 | 
						|
exports.unstable_wrapCallback = unstable_wrapCallback;
 | 
						|
          /* global __REACT_DEVTOOLS_GLOBAL_HOOK__ */
 | 
						|
if (
 | 
						|
  typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ !== 'undefined' &&
 | 
						|
  typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop ===
 | 
						|
    'function'
 | 
						|
) {
 | 
						|
  __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop(new Error());
 | 
						|
}
 | 
						|
        
 | 
						|
  })();
 | 
						|
}
 |