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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)^[a-zA-Z]\d{4}$" Local $sString = "# The CMS, who maintain these codes, describe the format as:-" & @CRLF & _ "# "HCPCS Level II codes (also known as alpha-numeric codes) consist of a single alphabetical letter followed by 4 numeric digits."" & @CRLF & _ "# (https://www.cms.gov/medicare/coding-billing/healthcare-common-procedure-system)" & @CRLF & _ "# NOTE: This regex will not identify HCPCS Level I codes (AKA CPT codes)" & @CRLF & _ "# Also, some sources say the single letter ranges only from A-V (this regex follows A-Z)" & @CRLF & _ "# Finally, this regex does not match procedure modifiers, which are 2 digit codes that follow a HCPCS code (with hyphen). " & @CRLF & _ "# (https://www.aapc.com/resources/what-are-medical-coding-modifiers)" & @CRLF & _ "# A separate regex has been created on regex101 supporting these modifiers" & @CRLF & _ "" & @CRLF & _ "# Genuine codes" & @CRLF & _ "E8015" & @CRLF & _ "A6410" & @CRLF & _ "C5278" & @CRLF & _ "G2102" & @CRLF & _ "M1221" & @CRLF & _ "V2623" & @CRLF & _ "V2756" & @CRLF & _ "c5278" & @CRLF & _ "g2102" & @CRLF & _ "m1221" & @CRLF & _ "v2623" & @CRLF & _ "v2756" & @CRLF & _ "# Should fail" & @CRLF & _ "EE8015" & @CRLF & _ "6410" & @CRLF & _ "E641O" & @CRLF & _ "[6410" & @CRLF & _ "_6510" & @CRLF & _ "g212" & @CRLF & _ "C52789" & @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