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

/
/
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 $sRegex = "(?m)^([A-z]+)(?: *= *)(\d+|[A-z]+)$" Local $sString = "Expression validator" & @CRLF & _ "^((?:[A-z]+)|((-|\+)?\d+))( +(\++|-+) +((?:-?\d+)|(?:[A-z]+)))*$" & @CRLF & _ "" & @CRLF & _ "Assignment validator" & @CRLF & _ "^([A-z]+)(?: *= *)(\d+|[A-z]+)$" & @CRLF & _ "" & @CRLF & _ "c= a" & @CRLF & _ "8" & @CRLF & _ "8 + 4" & @CRLF & _ "-2 + 4 - 5 + 6" & @CRLF & _ "" & @CRLF & _ "9 +++ - 10 -- 8" & @CRLF & _ "9 --- + 10" & @CRLF & _ "9 --- -10" & @CRLF & _ "9 +++ -10 -- 8" & @CRLF & _ "3 --- 5" & @CRLF & _ "14 - 12" & @CRLF & _ "-3 2" & @CRLF & _ "name = 44" & @CRLF & _ "a = 5" & @CRLF & _ "capName = 6 + 4" & @CRLF & _ "capName = 6" & @CRLF & _ "n = 3" & @CRLF & _ "m=4" & @CRLF & _ "a = 5" & @CRLF & _ "b = a" & @CRLF & _ "v= 7" & @CRLF & _ "n =9" & @CRLF & _ "c= a" & @CRLF & _ "A variable can have a name consisting of more than one letter." & @CRLF & _ "" & @CRLF & _ "count = 10" & @CRLF & _ "To print the value of a variable you should just type its name." & @CRLF & _ "" & @CRLF & _ "N = 5" & @CRLF & _ "N" & @CRLF & _ "5" & @CRLF & _ "It should be possible to set a new value to an existing variable." & @CRLF & _ "" & @CRLF & _ "a = 1" & @CRLF & _ "a = 2" & @CRLF & _ "a = 3" & @CRLF & _ "a" & @CRLF & _ "3" & @CRLF & _ "If an identifier or value of a variable is invalid, the program must print a message like the one below." & @CRLF & _ "" & @CRLF & _ "a1 = 8" & @CRLF & _ "Invalid identifier" & @CRLF & _ "n = a2a" & @CRLF & _ "Invalid assignment" & @CRLF & _ "a = 7 = 8" & @CRLF & _ "Invalid assignment" & @CRLF & _ "" & @CRLF & _ "" & @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