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/*
Examples From
JavaScript: The Definitive Guide, Fourth Edition
Legal matters: these files were created by David Flanagan, and are
Copyright (c) 2001 by David Flanagan. You may use, study, modify, and
distribute them for any purpose. Please note that these examples are
provided "as-is" and come with no warranty of any kind.
David Flanagan
*/
<!-- Check whether JavaScript 1.2 is supported. -->
<script language="JavaScript1.2">var _js12_ = 1.2</script>
<!-- Now avoid the problems with JavaScript 1.2 on Netscape by running -->
<!-- the following code on any browser that supports JavaScript 1.1. If -->
<!-- the browser does not support JavaScript 1.2, however, we'll display -->
<!-- an error message and suppress any syntax errors that occur. -->
<script language="JavaScript1.1">
// If JavaScript 1.2 is not supported, fail gracefully.
function supressErrors() { return true; }
if (!_js12_) {
window.onerror = supressErrors;
alert("This program requires a browser with JavaScript 1.2 support");
}
// Now proceed with the JavaScript 1.2 code.
</script>
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