Icard/angular-clarity-master(work.../node_modules/immediate/lib/browser.js

70 lines
1.8 KiB
JavaScript

'use strict';
var Mutation = global.MutationObserver || global.WebKitMutationObserver;
var scheduleDrain;
{
if (Mutation) {
var called = 0;
var observer = new Mutation(nextTick);
var element = global.document.createTextNode('');
observer.observe(element, {
characterData: true
});
scheduleDrain = function () {
element.data = (called = ++called % 2);
};
} else if (!global.setImmediate && typeof global.MessageChannel !== 'undefined') {
var channel = new global.MessageChannel();
channel.port1.onmessage = nextTick;
scheduleDrain = function () {
channel.port2.postMessage(0);
};
} else if ('document' in global && 'onreadystatechange' in global.document.createElement('script')) {
scheduleDrain = function () {
// Create a <script> element; its readystatechange event will be fired asynchronously once it is inserted
// into the document. Do so, thus queuing up the task. Remember to clean up once it's been called.
var scriptEl = global.document.createElement('script');
scriptEl.onreadystatechange = function () {
nextTick();
scriptEl.onreadystatechange = null;
scriptEl.parentNode.removeChild(scriptEl);
scriptEl = null;
};
global.document.documentElement.appendChild(scriptEl);
};
} else {
scheduleDrain = function () {
setTimeout(nextTick, 0);
};
}
}
var draining;
var queue = [];
//named nextTick for less confusing stack traces
function nextTick() {
draining = true;
var i, oldQueue;
var len = queue.length;
while (len) {
oldQueue = queue;
queue = [];
i = -1;
while (++i < len) {
oldQueue[i]();
}
len = queue.length;
}
draining = false;
}
module.exports = immediate;
function immediate(task) {
if (queue.push(task) === 1 && !draining) {
scheduleDrain();
}
}