#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?m)^((?:\d[+*]){0,49}\d)$"
Local $sString = "1+2*3*8+0" & @CRLF & _
"9" & @CRLF & _
"9*9" & @CRLF & _
"" & @CRLF & _
"the 99 character expression" & @CRLF & _
"" & @CRLF & _
"1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+5*8" & @CRLF & _
"" & @CRLF & _
"And these would not be valid:" & @CRLF & _
"" & @CRLF & _
"1++1" & @CRLF & _
"12+1" & @CRLF & _
"2*25" & @CRLF & _
"1+" & @CRLF & _
"47" & @CRLF & _
"+" & @CRLF & _
"+1" & @CRLF & _
"11" & @CRLF & _
"" & @CRLF & _
"100+ character length" & @CRLF & _
"" & @CRLF & _
"1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+1*2+5*8+9"
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