st: Executing mata drop within a do file after an if condition

[Thomas Jacobs <thomasjacobs@gmail.com>]

I am trying to drop a mata matrix within a do file while within the
mata environment but have been unable to get it to work.

Thus, I have a do file that begins in stata and at a point early on I have

mata:

then I attempt to execute the following:

mMemSave = strtoreal(st_global("MemSave"))

if (mMemSave > 0) mata drop FirmRawRet

yet I get:

invalid expression
r(3000);

I have checked that the if logic is correct in the immediate window
and have a similar line in many other locations of the program where
the result of the if condition is something different than mata drop.
I have also confirmed I can execute mata drop FirmRawRet from the
immediate window so I believe it is something related to mixing the if
with the mata drop command.

Can anyone enlighten me on what I am doing wrong here?  Thanks.

Tom

-- 
Thomas Jacobs
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