Possessive quantifiers are a way to prevent the regex engine from trying all permutations. This is primarily useful for performance reasons. You can also use possessive quantifiers to eliminate certain matches.
This tutorial will teach you how to create your own regular expressions, starting with the most basic regex concepts and ending with the most advanced and specialized capabilities.
Validate and benchmark your .NET regular expressions here in this lightweight Silverlight application. Your regular expression matches will be highlighted as you type.
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