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
Processing...

Test String

Code Generator

Generated Code

const regex = /(?x)(?(DEFINE) (?<AutoItString> "(?> [^"]+ | "" )*" # double quoted string | '(?> [^']+ | '' )*' # single quoted string ) # AutoIt string definition (?<CommentBlock> (?m) ^\h*\# (?>cs|comments-start)\b # start of comment block (?sU:(?>(?&CommentBlock)|.)*) # content of comment block (could be nested) ^\h*\#(?>ce|comments-end)\b.*\R # end of comment block ) (?<NonComment> (?> (?&AutoItString) | [^\;\r\n])* ) # anything what's not a single comment (?<SingleComment> (?m) ^ (?&NonComment)\K\;.*$) # a AutoIt single line comment (?<Comment> (?&CommentBlock) | (?&SingleComment) ) # all AutoIt comments (?<MultilineCmd> (?>_\h* (?>\;.*$)? [\r\n]*)+) (?<FuncName> ([\w_]+)) # function name (?<FuncDef> ^\h*Func(?:|\h|(?&MultilineCmd))+ (?&FuncName) (?:\h|(?&MultilineCmd))* (?=\() ) # function definition (?<BracketContent> \( (?> (?&BracketContent) | \;.*$ | (?&AutoItString) | \h*(?&MultilineCmd) | [^\;\r\n"'()]* )* \) ) ) (?&FuncDef)((?&BracketContent))/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?x)(?(DEFINE) (?<AutoItString> "(?> [^"]+ | "" )*" # double quoted string | \'(?> [^\']+ | \'\' )*\' # single quoted string ) # AutoIt string definition (?<CommentBlock> (?m) ^\\h*\\# (?>cs|comments-start)\\b # start of comment block (?sU:(?>(?&CommentBlock)|.)*) # content of comment block (could be nested) ^\\h*\\#(?>ce|comments-end)\\b.*\\R # end of comment block ) (?<NonComment> (?> (?&AutoItString) | [^\\;\\r\\n])* ) # anything what\'s not a single comment (?<SingleComment> (?m) ^ (?&NonComment)\\K\\;.*$) # a AutoIt single line comment (?<Comment> (?&CommentBlock) | (?&SingleComment) ) # all AutoIt comments (?<MultilineCmd> (?>_\\h* (?>\\;.*$)? [\\r\\n]*)+) (?<FuncName> ([\\w_]+)) # function name (?<FuncDef> ^\\h*Func(?:|\\h|(?&MultilineCmd))+ (?&FuncName) (?:\\h|(?&MultilineCmd))* (?=\\() ) # function definition (?<BracketContent> \\( (?> (?&BracketContent) | \\;.*$ | (?&AutoItString) | \\h*(?&MultilineCmd) | [^\\;\\r\\n"\'()]* )* \\) ) ) (?&FuncDef)((?&BracketContent))', 'gm') const str = `Func _CloseInputGUI(_Test(), _Test ( ) ) ; ENABLE \$g_hMainGUI; Eingegebene Daten uebernehmen, wenn kein Fehler bei der Eingabe (IP-Adresse) Func _ _SciTE_ShowFuncName() Func _SciTE_ShowFuncName () Func _SciTE_ShowFuncName ( ";" ) ; Func _SciTE_ShowFuncName (";"); Func _SciTE_ShowFuncName (";" _ _ ; und hier ein Kommentar , "hier geht es weiter"); Func _SciTE_ShowFuncName() Func _SciTE_ShowFuncName( (5+6) - (3*8)) Func _SciTE_ShowFuncName() ; () blabla Func _SciTE_ShowFuncName(_AddComment(";" & \$aComment[Random(0, 1, 1)])) ; () blabla Func _Strip(11, "Func _SciTE_ShowFuncName('Das hier ist ""böse"". ;)')")`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions