Regular Expressions 101

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  • Substitution
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  • Unit Tests (7)

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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

/
/
gim

Test String

Code Generator

Language

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?im)(?<=^ *)(?=\$(?:\{[a-z_][a-z0-9_]*\}|[a-z_][a-z0-9_]*)|[a-z_][a-z0-9_]*)(?:(?:\$\{)?([^ \}]+)\}?)(?= *$)" Local $sString = "### INFO" & @CRLF & _ "# Attempt to capture a parameter identifier inside a text selection, possibly" & @CRLF & _ "# wrapped in whitespace, including the following (examples using `backtick quotes`):" & @CRLF & _ "# - Raw word: e.g. `param_name`" & @CRLF & _ "# - $parameter expansion: e.g. `$param_name`" & @CRLF & _ "# - ${parameter} expansion e.g. `${param_name}`" & @CRLF & _ "### ENDINFO" & @CRLF & _ "" & @CRLF & _ "testvar" & @CRLF & _ " testvar" & @CRLF & _ " test_var " & @CRLF & _ " test5_var " & @CRLF & _ " test_var5 " & @CRLF & _ " $test_var" & @CRLF & _ " $test_var4" & @CRLF & _ " ${test_var4}" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

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