st: Evaluating a set of conditions

[Thomas Speidel <thomas@tmbx.com>]

I realize this is a very broad question and no one solution can fit  
all problems. I am looking for more efficient or elegant alternatives  
to evaluate a set of conditions in Stata, than a lenghty if qualifier.  
E.g.:

do something if A==1 & (B>2 & B<.) & (C==1 | D!=2)

these expression can become lengthy and one can think of more elegant  
ways to come to the same results.
cond and inrange are the first things that come to my mind that may  
(or may not) simplify the problem, but I hardly ever use them because  
understanding them (or remembering them) usually takes longer then  
writing the 'lengthy' qualifiers.
To complicate matters one has to account for missing values.   
Admittedly, this question came about from the recent topic on missing  
values.
If someone want to share an example, please do so.

--
Thomas Speidel

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