Introduction - If you have any usage issues, please Google them yourself
Just what is a regular expression, anyway? Take the tutorial to get the long answer. The short answer is that a regular expressionis a compact way of describing complex patterns in texts. You can use them to searchfor patterns and, once found, to modify the patterns in complex ways. You can also usethem to launch programmatic actions that depend on patterns.A tongue-in-cheek comment by programmers is worth thinking about: Sometimes youhave a programming problem and it seems like the best solution is to use regularexpressions now you have two problems. Regular expressions are amazinglypowerful and deeply expressive. That is the very reason writing them is just aserror-prone as writing any other complex programming code. It is always better tosolve a genuinely simple problem in a simple way when you go beyond simple, thinkabout regular expressions.Tutorial: Using regular expressions