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

/
/
g

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"(?s)([A-Z\()\h-]+):(.+?)(?=\n[A-Z\()\h-]+:|$)" test_str = ("AHK-VERSION:\n" "AutoHotkey_L 1.1.04 or later. Tested on: Windows 7 64bit, AutoHotkey 32bit Unicode 1.1.05.01.\n\n" "AUTHOR:\n" "?A_Samurai?\n\n" "DATE:\n" "?2011?\n\n" "DEPENDENCIES:\n" "none\n\n" "KEYWORDS:\n" "gui, activeX, html\n\n" "LICENSE:\n" "Public Domain\n\n" "LINK:\n" "---\n\n" "PARAMETER(S):\n" "Text : the text strings to display in the edit box.\n" "Title : the title for the GUI window.\n" "Timeout : if specified, the edit box will disappear in the given seconds.\n" "Permanent : if this is TRUE, closing the window does not destroy the window but hide it.\n" "So it can be displayed again with the window handle.\n" "GUIOptions : the options for the Edit box GUI window.\n" "ControlOptions : the options for the Edit control.\n" "Margin : the margin in pixels between the window borders and the control.\n\n" "REMARK(S):\n" "No global variables are used. However, it uses these label names: EditBoxClose, EditBoxEscape\n" "EditBoxResize. So the script should avoid using the label names.\n\n" "RETURN VALUE:\n" "The window handle (hwnd) of the created GUI window\n\n" "SYNTAX:\n" "EditBox(Text, Title=\"\", Timeout=0, Permanent=False, GUIOptions=\"Resize MaximizeBox Minsize420x320\", ControlOptions=\"VScroll W400 H300\", Margin=10)\n") matches = re.finditer(regex, test_str) 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