The bottom line of this blog post is that Internet Explorer incorrectly increments a regex object's lastIndex property after a successful, zero-length match. However, for anyone who isn't sure what I'm talking about or is interested in how to work around the problem, I'll describe the issue with examples of iterating over each match in [...]

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Here's one of the oddest and most significant regex bugs in Internet Explorer. It can appear when using optional elision within lookahead (e.g., via ?, *, {0,n}, or (.|); but not +, interval quantifiers starting from one or higher, or alternation without a zero-length option). An example in JavaScript: /(?=a?b)ab/.test("ab"); // Should return true, but IE 5.5 [...]

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Not all shorthand character classes and other JavaScript regex syntax is Unicode-aware. In some cases it can be important to know exactly what certain tokens match, and that's what this post will explore. According to ECMA-262 3rd Edition, \s, \S, ., ^, and $ use Unicode-based interpretations of whitespace and newline, while \d, \D, \w, \W, [...]

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This post isn't about the pros and cons of innerHTML vs. W3C DOM methods. That has been hashed and rehashed elsewhere. Instead, I'll show how you can combine the use of innerHTML and DOM methods to make your code potentially hundreds of times faster than innerHTML on its own, when working with large numbers of [...]

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Let's say you wanted to find all <div> tags, and capture their id and class attribute values. Anyone who's spent much time parsing HTML with regular expressions is probably aware that it can get quite tricky to match or capture multiple, specific attribute values with one regex, considering that the regex needs to allow for [...]

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