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

/
/
gimx

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 $sRegex = "(?imx)^ " & @CRLF & _ "# Uncomment to allow prefix continuation (second letter of a dangling match)" & @CRLF & _ "# ([abcdefghiklmnoprstuvy\ ])?" & @CRLF & _ "( \" & @CRLF & _ " |(?: # Single-letter elements" & @CRLF & _ " [BCFHIKNOPSUVWY]" & @CRLF & _ " )" & @CRLF & _ " |(?: # Two-letter elements." & @CRLF & _ " (?:A[cglmrstu])|(?:B[aehikr])|(?:C[adeflmnorsu])|(?:D[bsy])" & @CRLF & _ " | (?:E[rsu])|(?:F[elmr])|(?:G[ade])|(?:H[efgos])|(?:I[nr])" & @CRLF & _ " | (?:K[r])|(?:L[airuv])|(?:M[cdgnot])|(?:N[abdehiop])" & @CRLF & _ " | (?:O[gs])|(?:P[abdmortu])|(?:R[abefghnu])|(?:S[bcegimnr])" & @CRLF & _ " | (?:T[abcehilms])|(?:X[e])|(?:Yb)|(?:Z[nr])" & @CRLF & _ " )" & @CRLF & _ " |(?: # Smushed trigrams. No need to go past trigrams because two twos make four" & @CRLF & _ " (?:A(?:ga|gd|ge|la|lr|md|mg|mt|ra|re|rg|ta|te|tl|tm))" & @CRLF & _ " |(?:E(?:ra|re|rg))" & @CRLF & _ " |(?:G(?:ag|al|am|ar|at|er))" & @CRLF & _ " |(?:L(?:ag|al|am|ar|at|ra|re|rg))" & @CRLF & _ " |(?:M(?:ga|gd|ge|ta|te|tl|tm))" & @CRLF & _ " |(?:R(?:ag|al|am|ar|at|er|ga|gd|ge))" & @CRLF & _ " |(?:T(?:ag|al|am|ar|at|er|la|lr|md|mg|mt))" & @CRLF & _ " |(?:X(?:er))" & @CRLF & _ " |(?:Z(?:ra|re|rg))" & @CRLF & _ " )" & @CRLF & _ "# repeated any number of times" & @CRLF & _ ")+" & @CRLF & _ "# Uncomment to allow last letter if it's a potential first letter of the next word" & @CRLF & _ "# ([ADEGLMRTXZ]\ *)?" & @CRLF & _ "$" Local $sString = "**(See bottom for Javascript/one-line version)**" & @CRLF & _ "If you want continuation -- to look for "fez" "rave" "rites" chains, strike the second and second-to-last lines. Latex needs a suffix and ear needs a prefix." & @CRLF & _ "latex" & @CRLF & _ "ear" & @CRLF & _ "latexear" & @CRLF & _ "fez" & @CRLF & _ "rave" & @CRLF & _ "rites" & @CRLF & _ "fezraverites" & @CRLF & _ "if you don't want overlap, comment out the big group with (?<=..) tests. Walter and lag will not match: lag is La + Ag but can't be L+Ag or La+G; walter is W+Al+Te+Er but there's no single A, L, T, E or R to make it a strict chain of elements." & @CRLF & _ "Walter" & @CRLF & _ "aga" & @CRLF & _ "McLvinandfezrobHogwartsWizrdsofMoney" & @CRLF & _ "## Match:" & @CRLF & _ "McLvIn" & @CRLF & _ "McLvinandfezrobHogwartsWizrdsofMoney" & @CRLF & _ "zr" & @CRLF & _ "McLvinand" & @CRLF & _ "ergo" & @CRLF & _ "Orgasmicallabkitscashflow" & @CRLF & _ "update" & @CRLF & _ "Organicfurbies" & @CRLF & _ "Babkes" & @CRLF & _ "WalterWhite" & @CRLF & _ "That" & @CRLF & _ "ibexesnogladybirds" & @CRLF & _ "Xenophobic" & @CRLF & _ "picnicforgus" & @CRLF & _ "snapes" & @CRLF & _ "siriusblack" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "## match until last letter, and last letter potentially starts a new word (allows continuation)" & @CRLF & _ "fez" & @CRLF & _ "McLvinandfez" & @CRLF & _ "bobatea" & @CRLF & _ "" & @CRLF & _ "# La + At + Te" & @CRLF & _ "late" & @CRLF & _ "# the x awaits an e in the next word" & @CRLF & _ "latex" & @CRLF & _ "# N + Nd + Dy + Y + Yb" & @CRLF & _ "ndyb" & @CRLF & _ "# the a is a potential continuation" & @CRLF & _ "andy" & @CRLF & _ "# ...but the x can't be a second letter" & @CRLF & _ "xndyb" & @CRLF & _ "" & @CRLF & _ "## Don't Match at some interior point in line" & @CRLF & _ "Jemmamead" & @CRLF & _ "## Don't Match anywhere in line" & @CRLF & _ "JemmaQmead" & @CRLF & _ "" & @CRLF & _ "### For Javascript:" & @CRLF & _ "" & @CRLF & _ "^([abcdefghiklmnoprstuvy\s])?(\ |(?:[BCFHIKNOPSUVWY])|(?:(?:A[cglmrstu])|(?:B[aehikr])|(?:C[adeflmnorsu])|(?:D[bsy])|(?:E[rsu])|(?:F[elmr])|(?:G[ade])|(?:H[efgos])|(?:I[nr])|(?:K[r])|(?:L[airuv])|(?:M[cdgnot])|(?:N[abdehiop])|(?:O[gs])|(?:P[abdmortu])|(?:R[abefghnu])|(?:S[bcegimnr])|(?:T[abcehilms])|(?:X[e])|(?:Yb)|(?:Z[nr]))|(?:(?:A(?:ga|gd|ge|la|lr|md|mg|mt|ra|re|rg|ta|te|tl|tm))|(?:E(?:ra|re|rg))|(?:G(?:ag|al|am|ar|at|er))|(?:L(?:ag|al|am|ar|at|ra|re|rg))|(?:M(?:ga|gd|ge|ta|te|tl|tm))|(?:R(?:ag|al|am|ar|at|er|ga|gd|ge))|(?:T(?:ag|al|am|ar|at|er|la|lr|md|mg|mt))|(?:X(?:er))|(?:Z(?:ra|re|rg))))+([ADEGLMRTXZ]\ *)?$" 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