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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox Local $sRegex = "(?m)^([ ]{6})(- )((?!name)\w+[:](?:[ ]*(?=\n\1[ ]{4}\S)|[ ]*\S.+))((?:\n\1[ ]{2}.+)*?)(?:\n(\1[ ]{2})(name[ ]*[:])((?:[ ]*(?![>|])\S.+\b)|(?:(?:[ ]*[>|])?\n\5[ ]+.+)*))[ ]*$" Local $sString = "// YAML Textmate grammar name property hoister" & @CRLF & _ "// Moves a later `name` key value pair in multi value block definition to the " & @CRLF & _ "// top of its " & @CRLF & _ "//" & @CRLF & _ "// # Notes" & @CRLF & _ "// - Indent size is assumed to be 2." & @CRLF & _ "// - Indent level of names being hoisted is controlled by capture group $1," & @CRLF & _ "// which is later referenced by $5, the indent level of all other properties" & @CRLF & _ "// - Other properties can be hoisted by replacing the two instances of `name`" & @CRLF & _ "// in the pattern. A couple inputs for simple nested, folded, and literal values " & @CRLF & _ "// (immediately after these notes) seem to work." & @CRLF & _ "// - Syntax level comments in captures will probably need to be rearranged after " & @CRLF & _ "// applying this, and worst case (especially comments lower indents) break matching" & @CRLF & _ "" & @CRLF & _ " - match: '\s*(\,)\s*'" & @CRLF & _ " name:" & @CRLF & _ " 'Testing': Regex101.Debug.Nested.Name" & @CRLF & _ " - match: '\s*(\,)\s*'" & @CRLF & _ " name:" & @CRLF & _ " 'Testing': Regex101.Debug.Nested.Name.TrailingWhitespace " & @CRLF & _ " - match: '\s*(\,)\s*'" & @CRLF & _ " # Comment" & @CRLF & _ " name:" & @CRLF & _ " 'Testing': Regex101.Debug.Nested.Name.TrailingWhitespace " & @CRLF & _ " - match: '\s*(\,)\s*'" & @CRLF & _ " name: >" & @CRLF & _ " Wow this is a long name?" & @CRLF & _ " kind of sus" & @CRLF & _ " - match: '\s*(\,)\s*'" & @CRLF & _ " name: |" & @CRLF & _ " sus2" & @CRLF & _ " - name: meta.selector.stylus" & @CRLF & _ " match: '\s*(\,)\s*'" & @CRLF & _ " - match: \*" & @CRLF & _ " name: meta.selector.stylus " & @CRLF & _ " - match: '\s*(\&)([a-zA-Z0-9_-]+)\s*'" & @CRLF & _ " captures:" & @CRLF & _ " '2':" & @CRLF & _ " name: entity.other.attribute-name.parent-selector-suffix.stylus" & @CRLF & _ " name: meta.selector.stylus" & @CRLF & _ " - match: \s*(\&)\s*" & @CRLF & _ " name: meta.selector.stylus" & @CRLF & _ " - captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " match: '(\.)[a-zA-Z0-9_-]+'" & @CRLF & _ " name: entity.other.attribute-name.class.css" & @CRLF & _ " - captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " match: '(#)[a-zA-Z][a-zA-Z0-9_-]*'" & @CRLF & _ " name: entity.other.attribute-name.id.css" & @CRLF & _ " - captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " match: >-" & @CRLF & _ " (:+)(after|before|content|first-letter|first-line|host|(-(moz|webkit|ms)-)?selection)\b" & @CRLF & _ " name: entity.other.attribute-name.pseudo-element.css" & @CRLF & _ " - captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " match: >-" & @CRLF & _ " (:)((first|last)-child|(first|last|only)-of-type|empty|root|target|first|left|right)\b" & @CRLF & _ " name: entity.other.attribute-name.pseudo-class.css" & @CRLF & _ " - captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " match: >-" & @CRLF & _ " (:)(checked|enabled|default|disabled|indeterminate|invalid|optional|required|valid)\b" & @CRLF & _ " name: entity.other.attribute-name.pseudo-class.ui-state.css" & @CRLF & _ " - begin: '((:)not)(\()'" & @CRLF & _ " beginCaptures:" & @CRLF & _ " '1':" & @CRLF & _ " name: entity.other.attribute-name.pseudo-class.css" & @CRLF & _ " '2':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " '3':" & @CRLF & _ " name: punctuation.section.function.css" & @CRLF & _ " end: \)" & @CRLF & _ " endCaptures:" & @CRLF & _ " '0':" & @CRLF & _ " name: punctuation.section.function.css" & @CRLF & _ " patterns:" & @CRLF & _ " - include: '#selector'" & @CRLF & _ " - captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: entity.other.attribute-name.pseudo-class.css" & @CRLF & _ " '2':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " '3':" & @CRLF & _ " name: punctuation.section.function.css" & @CRLF & _ " '4':" & @CRLF & _ " name: constant.numeric.css" & @CRLF & _ " '5':" & @CRLF & _ " name: punctuation.section.function.css" & @CRLF & _ " match: >-" & @CRLF & _ " ((:)nth-(?:(?:last-)?child|(?:last-)?of-type))(\()(\-?(?:\d+n?|n)(?:\+\d+)?|even|odd)(\))" & @CRLF & _ " - match: '((:)dir)\s*(?:(\()(ltr|rtl)?(\)))?'" & @CRLF & _ " captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: entity.other.attribute-name.pseudo-class.css" & @CRLF & _ " '2':" & @CRLF & _ " name: puncutation.definition.entity.css" & @CRLF & _ " '3':" & @CRLF & _ " name: punctuation.section.function.css" & @CRLF & _ " '4':" & @CRLF & _ " name: constant.language.css" & @CRLF & _ " '5':" & @CRLF & _ " name: punctuation.section.function.css" & @CRLF & _ " - match: '((:)lang)\s*(?:(\()(\w+(-\w+)?)?(\)))?'" & @CRLF & _ " captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: entity.other.attribute-name.pseudo-class.css" & @CRLF & _ " '2':" & @CRLF & _ " name: puncutation.definition.entity.css" & @CRLF & _ " '3':" & @CRLF & _ " name: punctuation.section.function.css" & @CRLF & _ " '4':" & @CRLF & _ " name: constant.language.css" & @CRLF & _ " '6':" & @CRLF & _ " name: punctuation.section.function.css" & @CRLF & _ " - captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " match: '(:)(active|hover|link|visited|focus)\b'" & @CRLF & _ " name: entity.other.attribute-name.pseudo-class.css" & @CRLF & _ " - captures:" & @CRLF & _ " '1':" & @CRLF & _ " name: punctuation.definition.entity.css" & @CRLF & _ " match: '(::)(shadow)\b'" & @CRLF & _ " name: entity.other.attribute-name.pseudo-class.css" Local $sSubst = "$1$2$6$7\n$5$3$4" 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