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POHow does jQuery's synchronous AJAX request work?
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copied!<p>Does <code>jQuery.ajax({async: false})</code> still use the XMLHttpRequest object?</p> <p>If so, how is the request synchronous?</p> <p>Is there just some mechanism inside the function definition that allows the asynchronous request put out by the XHR to be wrapped in a synchronous wrapper?</p> <p>I ask because I want to wrap asynchronous function calls into a synchronous wrapper.</p> <p><strong>EDIT</strong>:</p> <p>I want to do this for dependencies. I need to not run anything more until all the external dependency scripts are loaded, however, I'd rather not load each of the files synchronously.</p> <p>Basically, I want this:</p> <pre><code>require(['lib1.js','lib2.js']) Library1Function(); Library2Function(); </code></pre> <p>To load lib1 and lib2 at the same time, but block until both are loaded.</p> <p>I know I could do this with a callback, however that doesn't work if the files I'm including also have dependencies included in the same way.</p> <p><strong>EDITx2</strong></p> <p>Reason why callbacks don't work:</p> <pre><code># lib2.js window.Library2Function = function(input) { alert(input); } # lib1.js require('lib2.js', function() { window.Library1Function = function() { window.Library2Function('Hi there'); } }); # main.js require('lib1.js', function() { window.Library1Function(); }); </code></pre> <p>The problem is that, in main.js, that callback will get sent off once lib1.js is loaded and run. The problem is, <code>Library2Function</code> isn't actually defined until lib2.js is loaded, which happens <em>after</em> lib1.js is parsed.</p>

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