#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m)((<CnlNum>)|(Val\s?\())([5-9])(\d{2})((?(2)</CnlNum>|\),\s?))"
Local $sString = " <CnlNum>548</CnlNum>" & @CRLF & _
" GetBit(Val(548), 3)" & @CRLF & _
"<CnlNum>548),"
Local $sSubst = "($1)1$4$5$6"
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