Best Regular Expression Dev Tools
Just a quick post to point out some fantastic web applications to help you craft regular expressions in your text processing adventures. These tools make it vastly easier to develop a solid understanding of regular expressions compared to when I learned them by studying the classic O'Reilly book Mastering Regular Expressions
First Place: RegEx 101
RegEx 101 is the overall best tool. The explanation block clearly explains how each part of your regular expression is interpretted. The syntax highlighting is great, and the UI doesn't have any confusing parts about whether you need the surrounding slashes and so forth.
Olaf Neumann Regex-Generator is a brilliant tool that starts with your input text, autosuggests common patterns, and guides you through building your regex.
RegExplained has a great railroad diagram visualization of your regular expression.
regexr is also handy although not as polished as RegEx 101.
Regex Tester has a nice railroad diagram and color coding.
debuggex Neat but no one wants to log into a utility site like this (needed to add unit tests)
Simple Regex is kind of like literate programming for regex. It's a different language you write with clearer expressions like
any of (digit, letter, one of ".-") once or more and it compiles to regex is several mainstream programming languages.
Get out there and be glad you may be able to get away without staring at the pages of this book for hours on end.