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
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • 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

/
/
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"^2$" test_str = ("# ___ ___ ___ ___ ___ \n" "# | _ )_ ) __| / __| __ _ _ ___ ___ _ _ | _ \\___ ___\n" "# | _ \\/ /\\__ \\ \\__ \\/ _| '_/ -_) -_) ' \\| / -_|_-<\n" "# |___/___|___/__|___/\\__|_| \\___\\___|_||_|_|_\\___/__/\n" "# |_ _| __| \\/ | _ \\ | /_\\_ _| __| \n" "# | | | _|| |\\/| | _/ |__ / _ \\| | | _| \n" "# |_| |___|_| |_|_| |____/_/ \\_\\_| |___| \n" "# \n" "# PLEASE MODIFY FOR YOUR OWN USAGE\n" "# Playfield Screen resolution width/height\n" "1920\n" "1080\n" "# Backglass Screen resolution width/height\n" "1280\n" "1024\n" "# Define Backglass using Display Devicename screen number (\\\\.\\DISPLAY)x or screen coordinates (@x) or screen index (=x)\n" "2\n" "# x position For the backglass relative To the upper left corner Of the Playfield screen\n" "0\n" "# y position For the backglass On the selected display (Normally left at 0)\n" "0\n" "# width/height Of the DMD area In pixels - For 3 screen setup\n" "551\n" "189\n" "# X/Y position Of the DMD area relative To the upper left corner Of the backglass screen - For 3 screen setup\n" "367\n" "813\n" "# Y-flip, flips the LED display upside down\n" "0\n" "# X/Y position pos When StartBackground Is active, relative To upper left corner Of Playfield ('Small' Button In the Options)\n" "0\n" "0\n" "# width/height Of the backglass When StartBackground Is active\n" "0\n" "0\n" "# C:\\path\\Frame (The path To the location where you have the background image)\n\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