st: macro of macros?

[Maria Ana Vitorino <vitorino@wharton.upenn.edu>]

Dear statalist users,
I've only recently started experimenting with macros and I have the  
following question: can we have a macro of macros and loop through the  
different sub-macros without having to set beforehand  how many sub- 
macros there are in the macro? Maybe it's easier to understand what  
I'm looking for with an example:

I know that the following can be done:

local set1 "x1 x2"
local set2 "x2 x3"
local sets ""`set1'" "`set2'""  ***

foreach xvars of local sets {
reg y xvars
}

But, instead of having to list all the macros in the line ***, can we  
have something like:

local set1 "x1 x2"
local set2 "x2 x3"

local sets ""`set'*""

foreach xvars of local sets {
reg y xvars
}


Ideally I would like to add (or remove) sets as a please so I wouldn't  
like to have to keep updating the line *** everytime I do so...

Any suggestions are appreciated.

thanks,
Ana
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