Re: st: Using arguments in a global macro

[David Kantor <kantor.d@att.net>]

At 08:17 PM 2/9/2014, Kate Ivanoval wrote:
> Hello,
>
> I am interested whether it is possible to include a command line argument in
> a global macro. So far, I have tried to do that but it does not seem to
> work. What I have looks approximately like this:
>
> global x "var1 var2 `var'"
> program prog1
>                args var
>                gen var3=1
>                reg depvar $x, noconstant
> end
> prog1 var3
>
> My "var3" variable is actually not a constant but I just used the simplest
> example to illustrate my point. When I run this program, I get the
> regression results but "var3" is simply omitted.
>
> I would appreciate any help with this. If I need to clarify my question,
> please let me know.
>
> Kate

x was assigned its value before prog1 was defined, and certainly 
before prog1 was invoked. At the time that x was assigned its value, 
var was empty. So you got what you asked for -- not what you meant to ask for.

If you move the assignment to x so it is inside prog1, after -args 
var-, then it should work as expected.

But presumably, you really want to have the assignment of x right 
where you put it, but arranged so that it evaluates var at a later 
point. You may be able to use delayed-evaluation. This works for 
locals; I've never tried it with globals, but I don't see why it 
wouldn't work. Leave the assignment of x where you have it. But put a 
"\" before `var' -- thus:

global x "var1 var2 \`var'"

That will probably work.
HTH
--David

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