Search text

2 snippets across 2 stacks — Bash & Linux, Python

SHBash & Linux

Search Text with Patterns

syntax

grep [options] pattern [file...]

example

grep -rn 'TODO' src/
grep -i 'error' /var/log/syslog
grep -c 'SELECT' queries.sql
grep -v '^#' nginx.conf

output

src/api/handler.go:42:  // TODO: add rate limiting
src/lib/cache.ts:18:  // TODO: implement TTL

Note -r searches recursively through directories. -n shows line numbers. -i is case-insensitive. -v inverts the match (shows non-matching lines). -c counts matches. -l lists only filenames with matches. Use -E for extended regex or egrep.

PYPython

re (Regular Expressions)

PY · Common Standard Library

syntax

import re
re.search(pattern, string)
re.findall(pattern, string)

example

import re

text = "Contact: [email protected] or [email protected]"
emails = re.findall(r"[\w.]+@[\w.]+\.\w+", text)
print(emails)

# Named groups
log = "2026-04-04 ERROR: Connection timeout"
match = re.match(r"(?P<date>[\d-]+) (?P<level>\w+): (?P<msg>.+)", log)
if match:
    print(match.group("level"), match.group("msg"))

output

['[email protected]', '[email protected]']
ERROR Connection timeout

Note Always use raw strings (r'...') for regex patterns. For repeated use, compile with re.compile() for performance. Use re.VERBOSE for readable multi-line patterns.