Total newb here. I'm trying to get a handle on conditional statements in NSIS.
I want to check if a previous installation of a program exists and go from there:
; parse registry information to determine if program is already installed
ReadRegStr $0 HKLM "System\ControlSet001\Control\Session Manager\Environment" "EIDMS"
$(If) $0 == ""
MessageBox MB_YESNOCANCEL "C:\SomeProg has not been created. Would you like to create it now?"
MessageBox MB_YESNOCANCEL "A previous version of SomeProg has been detected. Would you like to keep the settings?"
I included LogicLib.nsh, yet when I compile I receive the error: "Invalid command: $(If)"
Syntax problems or logic problems? Thanks for your help.