'if Variable MYVAR not is Defined' -> Compile Error

[jsmith]

If I add to my MSIcode:

Code: Select all

If Variable MYVAR not is Defined
  Set Variable MYVAR to some value
end

then click the compile button, I get a Compile Error: "Variable not defined: MYVAR." Yeah, I know. That's what I was testing for. Is this how this is supposed to work?

[Tinus]

This command requires a persistent variable!

if Variable MYVAR not is Defined
Set Persistent Variable MYVAR to
end

[jsmith]

I see, thanks! I don't want the value to persist, though. What I was trying to do was check if a value was passed in on the command line, and set it to a default value if it wasn't. The solution I found in another thread was to do this:

Code: Select all

if Variable CMDLINE not Contains (Ignore Case) MYVAR=
  Set Variable MYVAR to some value
end

It's not exactly elegant given that I could reference the value of MYVAR if it was passed in on the command line, but it works.