Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^(?P<disabled># *)?(?P<min>\*/\d+|\*|(?:\d+,?)+)(?: )(?P<hour>\*/\d+|\*|(?:\d+,?)+)(?: )(?P<day>\*/\d+|\*|(?:\d+,?)+)(?: )(?P<month>\*/\d+|\*|(?:\d+,?)+)(?: )(?P<dayofweek>\*/\d+|\*|(?:\d+,?)+)" test_str = ("PATH=/home/minecraft/.virtualenvs/charfred/bin:/usr/local/bin:/bin:/usr/bin:/home/minecraft/bin:/usr/local/sbin:/usr/sbin\n\n" "# Don't touch the above, pretty please!\n" "# =====================================================================\n" "# === These are my jobs, they may not be pretty, but they are mine. ===\n" "# =====================================================================\n" "#\n" "# This first one is an example job for the replacement to STC_Control:\n" "#\n" "# */5 * * * * spiffy status Revelation >> /home/minecraft/logs/test.log 2>&1\n" "#\n" "# =====================================================================\n" "# Variables here! Less typing, more lazy!:\n\n" "# Paths to log directories:\n" "ETERNALLOGS=/home/minecraft/logs/Eternal\n" "ETERNALVIPLOGS=/home/minecraft/logs/EternalVIP\n" "REVELATIONLOGS=/home/minecraft/logs/Revelation\n" "ENIGMATICALOGS=/home/minecraft/logs/Enigmatica\n" "BUNGEELOGS=/home/minecraft/logs/Bungee\n" "BACKUPLOGS=/home/minecraft/logs/Backups\n" "CHARFREDLOGS=/home/minecraft/logs/Charfred_III\n" "PO3LOGS=/home/minecraft/logs/PO3\n" "DDSSLOGS=/home/minecraft/logs/DDSS\n" "BURIEDLOGS=/home/minecraft/logs/Buried\n" "DIREWOLF147LOGS=/home/minecraft/logs/Direwolf147\n" "TFCRLOGS=/home/minecraft/logs/TFCR\n\n" "# ================\n" "# Real jobs below:\n" "# == ~~~~~~~~~~ ==\n\n" "# -~- Start Servers on Reboot -~-\n" "@reboot spiffy start Eternal >> $ETERNALLOGS/startup.log 2>&1\n" "@reboot spiffy start EternalVIP >> $ETERNALVIPLOGS/startup.log 2>&1\n" "@reboot spiffy start Revelation >> $REVELATIONLOGS/startup.log 2>&1\n" "@reboot spiffy start Enigmatica >> $ENIGMATICALOGS/startup.log 2>&1\n" "@reboot spiffy start PO3 >> $PO3LOGS/startup.log 2>&1\n" "@reboot spiffy start DDSS >> $DDSSLOGS/startup.log 2>&1\n" "# @reboot spiffy start Buried >> $BURIEDLOGS/startup.log 2>&1\n" "# @reboot spiffy start Direwolf147 >> $DIREWOLF147/startup.log 2>&1\n\n" "# -~- Server Online Keeper -~-\n" "*/15 * * * * spiffy start Eternal >> $ETERNALLOGS/failsafe.log 2>&1\n" "*/15 * * * * spiffy start EternalVIP >> $ETERNALVIPLOGS/failsafe.log 2>&1\n" "*/15 * * * * spiffy start Revelation >> $REVELATIONLOGS/failsafe.log 2>&1\n" "*/15 * * * * spiffy start Enigmatica >> $ENIGMATICALOGS/failsafe.log 2>&1\n" "# */15 * * * * spiffy start PO3 >> $PO3LOGS/failsafe.log 2>&1\n" "*/15 * * * * spiffy start DDSS >> $DDSSLOGS/failsafe.log 2>&1\n" "# */15 * * * * spiffy start Buried >> $BURIEDLOGS/failsafe.log 2>&1\n" "# */15 * * * * spiffy start Direwolf147 >> $DIREWOLF147LOGS/failsafe.log 2>&1\n\n" "# -~- Scheduled Restarts -~-\n" "0 7,19 * * * spiffy restart Revelation 10m >> $REVELATIONLOGS/restarts.log 2>&1\n" "0 8,14,20,2 * * * spiffy restart Enigmatica 10m >> $ENIGMATICALOGS/restarts.log 2>&1\n" "0 5,9,13,17,21,1 * * * spiffy restart DDSS 10m >> $DDSSLOGS/restarts.log 2>&1\n" "30 2,8,14,20 * * * spiffy restart PO3 10m >> $PO3LOGS/restarts.log 2>&1\n" "30 5,9,13,17,21,1 * * * spiffy restart Eternal 10m >> $ETERNALLOGS/restarts.log 2>&1\n" "30 3,11,19 * * * spiffy restart EternalVIP 10m >> $ETERNALVIPLOGS/restarts.log 2>&1\n\n\n" "# -~- World Backups -~-\n" "# ===== Info =====\n" "# Each backup takes about 4 minutes on the larger worlds and taxes one CPU core to 100%;\n" "# If multiple servers are specified in the same command, they'll be done sequentially,\n" "# meaning that backing up 4 servers in one command will take about 16min total.\n" "# === End Info ===\n" "0,10,20,30 0,4,8,12,16,20 * * * spiffy backup PO3 >> $BACKUPLOGS/po3.log 2>&1\n" "30 0,4,8,12,16,20 * * * spiffy backup DDSS >> $BACKUPLOGS/DDSS.log 2>&1\n" "# 0 1,5,9,13,17,21 * * * spiffy backup Direwolf147 >> $BACKUPLOGS/Direwolf147.log 2>&1\n" "30 1,5,9,13,17,21 * * *spiffy backup Revelation >> $REVELATIONLOGS/Revelation.log 2>&1\n" "# 0 2,6,10,14,18,22 * * * spiffy backup Buried >> $BACKUPLOGS/buried.log 2>&1\n" "30 2,6,10,14,18,22 * * * spiffy backup Enigmatica >> $BACKUPLOGS/enigmatica.log 2>&1\n" "0 3,7,11,15,19,23 * * * spiffy backup Eternal >> $BACKUPLOGS/eternal.log 2>&1\n" "15 1,5,9,13,17,21 * * * spiffy backup EternalVIP >> $BACKUPLOGS/eternalvip.log 2>&1\n\n" "# -~- Quest Backups -~-\n" "*/15 * * * * spiffy questbackup DDSS >> $BACKUPLOGS/quests.log 2>&1\n" "*/15 * * * * spiffy questbackup PO3 >> $BACKUPLOGS/quests.log 2>&1\n" "*/15 * * * * spiffy questbackup Enigmatica >> $BACKUPLOGS/quests.log 2>&1\n" "*/15 * * * * spiffy questbackup Eternal >> $BACKUPLOGS/quests.log 2>&1\n" "*/15 * * * * spiffy questbackup EternalVIP >> $BACKUPLOGS/quests.log 2>&1\n\n" "# -~- Charfred_III related Jobs -~-\n" "@reboot /home/minecraft/charloader.zsh\n\n" "# -~- inotify watcher for betterquesting -~-\n" "# @reboot screen -h 100 -dmS charredobserverI /home/minecraft/directorywatchforjinspleasure.zsh\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html