Flagrant Badassery

A JavaScript and regular expression centric blog

Archive for December, 2007

JavaScript Password Validation

Since I've seen tons of password validation help requests on regexadvice.com (where I hang out from time to time), I've written up a more general-purpose JavaScript password validation function. It's reasonably straightforward, and covers the validation requirements I've most frequently encountered. Plus, if it doesn't handle your exact needs, its functionality can be augmented by […]

Read More

/(bb|[^b]{2})/

…That is the question. ThinkGeek is selling that on a t-shirt for the "regular expression junkie + lover of literature." Wearing that around would be a sure way to get me to notice you, especially if you have a nice rack or happen to be Angelina Jolie. Note that the parentheses are unnecessary except in […]

Read More

Performance of Greedy vs. Lazy Regex Quantifiers

A common misconception about regular expression performance is that lazy quantifiers (also called non-greedy, reluctant, minimal, or ungreedy) are faster than their greedy equivalents. That's generally not true, but with an important qualifier: in practice, lazy quantifiers often are faster. This seeming contradiction is due to the fact that many people rely on backtracking to […]

Read More