st: manipulating string variables

[Jean Eid <jeaneid@chass.utoronto.ca>]

I have been trying to do the following with no luck (This is a 
simplification rather than exact procedure needed)

Suppose I declare a global variable
global myglobal "hello world, how are you today"

now what I want to do is the following:
a) see whether the string text today exist in $myglobal
b) replace "today" by "tomorrow"
c) instead of "are" I need to change the "a" to "b" let's say.

I know this does not make sense to you right now but I have all these 
regressions defined as global variables and need to manipulate them.

Can this be done in Stata?

I have checked strmatch and the likes but am not able to work it. I am 
looking for something like grep, sub and the likes in Linux.

If you know how to do this Please provide a workable example.


Thank you for your time

Jean

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