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

/
/
g

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "[^\w](?<!->)(trans|trans_choice|Lang::get|Lang::choice|Lang::trans|Lang::transChoice|@lang|@choice|__)\s*\(\s*((?<![\\])['"])((?:.(?!(?<![\\])\2))*.?)\2\s*[,\)]" Local $sString = "Should match variations on method:" & @CRLF & _ "trans('a.b');" & @CRLF & _ "trans_choice('a.b')" & @CRLF & _ "Lang::get('a.b');" & @CRLF & _ "Lang::choice('a.b', 1);" & @CRLF & _ "Lang::trans('a.b');" & @CRLF & _ "Lang::transChoice('a.b', 2);" & @CRLF & _ "@lang('language.line')" & @CRLF & _ "@choice('language.line', 1);" & @CRLF & _ "__('a.b')" & @CRLF & _ "" & @CRLF & _ "Should match variations of contained string" & @CRLF & _ "trans('key'); // No group, so JSON style" & @CRLF & _ "__('Json string')" & @CRLF & _ "trans('a.b');" & @CRLF & _ "trans('a.b.c');" & @CRLF & _ "trans('a_b.c-d');" & @CRLF & _ "trans('a.b!');" & @CRLF & _ "trans('a.translate me!');" & @CRLF & _ "trans('a.über~');" & @CRLF & _ "trans("app.i'm"); // contained quote of different type" & @CRLF & _ "trans('app."ok"');" & @CRLF & _ "trans('with contained " quotes');" & @CRLF & _ "trans('with an escaped \' quote')" & @CRLF & _ "trans('with a double \\')" & @CRLF & _ "" & @CRLF & _ "Should match additional variables and whitespace" & @CRLF & _ "trans('a.b', [1,2]);" & @CRLF & _ "trans ( " & @CRLF & _ " ' with whitespace ' , $var)" & @CRLF & _ "" & @CRLF & _ "Typical use cases" & @CRLF & _ "(trans ( 'lang.line'));" & @CRLF & _ "<span>@lang('lang.line')</span>" & @CRLF & _ "" & @CRLF & _ "Should not match:" & @CRLF & _ "trans($var); // No quotes" & @CRLF & _ "trans(); // Nothing" & @CRLF & _ "anytrans('group.key'); // not the method we need" & @CRLF & _ "1trans('lang.file'); // not the method" & @CRLF & _ "_trans('lang.file'); // not the method" & @CRLF & _ "->trans('lang.line');" & @CRLF & _ "trans(\'why do we have an escaped quote here?\')" & @CRLF & _ "trans('with a triple \\\') <-- fail!" & @CRLF & _ "trans('lang.line' . $middle); // concatenated vars" & @CRLF & _ "trans('lang.line' . $middle . '.ending'); // concatenated vars" & @CRLF & _ "___('hello') // not the method we need" & @CRLF & _ "" 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