NAME Wait - A missing shortcuts in JavaScript language. SYNOPSIS JSAN.use('Wait'); wait( // Wait for this function to return true function() { return (v1 == 100); }, // ... and then do this function() { v2 = true; }, // ... unless the waiting is so long function() { v3 = false; }, // ... as 10000 ms. 10000 ); DESCRIPTION This library exports a function called 'wait'. It aims to simplify the standard setInterval-clearInterval pattern which is used to ensure the synchronous of data. One basic problem programming in javascript is about asynchrounous, especially when you're dealing with cross browser issue. Sometimes the returned object of "document.createElement('div')" may not have it's ".style" property ready when you want to use it. So here's what 'wait' does: It keeps checking whether a given etst passed or not periodically. Once the test passed, call the callabck. If the waiting time is too long, longer then the maximum, another failure callback is called. The 'wait' function can be used in two form: either with 3 arguments or 4 arguments. The semantic of its 3-argument form is: wait(test, callback, max_wait) And for its 4-argument form, it would be: wait(test, callback, failure_callback, max_wait) It handles "setInterval()" and calls "clearInterval()" once the test passed, or elapsed over max waiting time. You may omit the last "max_wait" argument, in such case it never ends waiting, which means the "failure_callback" would never be called even if it's given. So you might just use this form for convienence: wait(test, callback) Waiting indefinitely might not be the best behaviour, but long as you can ensure that the test would be passing, it's golden. AUTHOR Kang-min Liu . COPYRIGHT Copyright 2006 by Kang-min Liu . This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See