Question

I don’t know if this is a know problem in IE8, but I can’t really find any info on it.

// The regex can vary but has to have a non-matching group defined:
var re = /^(\s)?[\d]+$/i;
// We call it with a string...
re.exec("2");
// We call it with a number...
re.exec(2);

Firefox and Chrome (can’t try it in Opera right now) have no problem with either calls. But on IE8 the second call fails with an “Object does not support that property or method”.

Is this a known bug or something?

Answer 1

I saw the same issues in an Ext JS 4 application. Lots of things were failing as Ext JS appears to pass numbers in the exec() method at times. The issue turned out to be a third party library SyntaxHighlighter. Removing this reverted the default IE8 behavior and re.exec(2); worked.

I’d suggest cutting down the external JS that you include in your app until you find the culprit.