Python Regular Expressions

Source code for Python Tutorial for Beginners #26 - Regular Expressions.

Files

• regex_basics.py — re.search(), re.match(), re.findall(), raw strings, metacharacters (\d, \w, \s)
• patterns_groups.py — Character classes, quantifiers, capturing groups, named groups, re.sub(), re.compile()
• text_processor.py — Mini project: email validation, phone extraction, log parsing, text cleanup

Running

python3 regex_basics.py
python3 patterns_groups.py
python3 text_processor.py

Topics Covered

• The re module for pattern matching
• re.search() to find patterns anywhere in text
• re.match() to check the start of a string
• re.findall() to extract all occurrences
• Raw strings (r"...") to keep backslashes literal
• Metacharacters: \d, \w, \s, ., ^, $
• Character classes [a-z] and negation [^0-9]
• Quantifiers: *, +, ?, {n}, {n,m}
• Capturing groups () and named groups (?P<name>...)
• re.sub() for substitution
• re.compile() for reusable patterns