Cannot pass global macro in "foreach"

[Claire P. Zheng]

Hi, I'm working on a project that applies the same set of analysis to each of the fifty states. So, I want to automate the process, which doesn't seem complicated using STATA's built-in "foreach" loop. I setup a global macro, which are the abbrv.s of the state names. However, I'm having trouble pass the macro. My code looks like:

* all files are in the working directory

global states "CA DE ... "

foreach state of global states {
use ${state}xxx.dta, clear

do dofilename1.do
do dofilename2.do
...
}

Stata didn't seem to recognize "${state}". I couldn't even open the data file in the main script. If I instead used `state' (the single-quotation for a local macro), Stata would read and open the data file. However, I couldn't pass the macro `state' to the following do files (since it's "local"). I swear to god the above code worked at some point. Then, it failed for no reason. I'm using Stata 11. How can I resolve this issue? I've been struggling on this and trying to find a solution for a whole day, but no luck. Really appreciate your help!!!

[Nick Cox]

The key here is although you defined a global called states, the entity state used in your loop is local to the loop and not global at all. So the only logical syntax is

foreach state of global states {
use `state'xxx.dta, clear

}

To pass each name to the do-file, pass it as an argument

do filename1 `state'

and at the top of each do-file have a definition something like

local state `1'

and refer to that local within the do-file.

Despite your fervour, I don't believe that your code as cited here ever worked, because what is true now was always true. I can't comment on anything you tried but did not report.