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

/
/
gms

Test String

Substitution

Processing...

Code Generator

Generated Code

#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox Local $sRegex = "(?ms)(?x)" & @CRLF & _ ".+(?:Sub|Function)\ (\w+)\( # method declaration" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "(?: # start of parameter pattern" & @CRLF & _ "[\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords" & @CRLF & _ "([a-z]\w+)+ # parameter starts with a lower case" & @CRLF & _ ".*? # parameter may be followed by its type declaration" & @CRLF & _ "(?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call" & @CRLF & _ "(?:,|\)) # parameter is followed by , or )" & @CRLF & _ "){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters)" & @CRLF & _ "" Local $sString = "Public Sub FindDictTreeNodes(ByVal startAtNodeDict As Scripting.Dictionary, ByVal searchKey As Variant, ByVal searchKeyItem As Variant, _" & @CRLF & _ " ByVal result As Collection, Optional ByVal childrenKey As Variant = "Children", Optional ByVal findOnlyFirst As Boolean, _" & @CRLF & _ " Optional ByVal searchAtLevel As Integer = 0, Optional ByVal useLikeOperatorForMatching As Boolean = False, _" & @CRLF & _ " Optional ByVal nowAtLevel As Integer)" & @CRLF & _ "" Local $sSubst = "#CSV list of parameters\n${2}, ${4}, ${6}, ${8}, ${10}, ${12}, ${14}, ${16}, ${18}, ${20}, ${22}, ${24}, ${26}, ${28}, ${30}\n\n#vertical list of parameters\n'${2} - \n'${4} - \n'${6} - \n'${8} - \n'${10} - \n'${12} - \n'${14} - \n'${16} - \n'${18} - \n'${20} - \n'${22} - \n'${24} - \n'${26} - \n'${28} - \n'${30} - \n" Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst) MsgBox($MB_SYSTEMMODAL, "Result", $sResult)

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm