Python Regex: Patterns I Actually Use in Production
Regular expressions are powerful and easy to overuse. After years of parsing logs and validating input, these are the patterns worth keeping. I have a love-hate relationship with regular expressions. They solve text-processing problems in a single line that would take dozens of lines of string methods. They also create unreadable monsters that no one on the team understands six months later. After years of using regex in production, I have settled on a set of patterns that are worth the complexity and habits that keep the complexity manageable. Compiling for Reuse The re module lets you use patterns as strings or compile them into pattern objects. For patterns used repeatedly, compiling is faster because the regex is parsed once. I compile patterns at module level so they are ready when the module loads. import re EMAIL_RE = re.compile(r'^[\w.+-]+@[\w-]+\.[\w.-]+