#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?im)(^nvsm)(\-)(apis|dshm|cli)(\-|\_)(\d{2}|\(\d{2}\))(\.)(0?[1-9]|1[012])(\.|\-)(\d{1}|\d{2})(\-|\_|\.)(\d{1}|\d{2}|all|el\d{1})(\.)(el\d{1}|(deb)|(noarch))(|(\.)((x86_64)|(rpm))(\.)(rpm))$"
Local $sString = "nvsm-dshm-18.12-2.el7.noarch.rpm"
Local $sSubst = "$1"
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