RE: Modify caller or callee?

Oh, it's a sign!!!

If admit() is never meant to handle long-haired freaky people, then the
modification belongs in admit(), and probably an error should be thrown.

If it is possible that admit() may be exposed for other modules, and those
modules might someday need admit() to handle such as that, the modification
belongs at the caller level. (But beware of those who may tuck their hair
up under their hat.)

Dennis Lovelady
http://www.linkedin.com/in/dennislovelady
--
"Don't knock the weather; nine tenths of the people couldn't start a
conversation if it didn't change once in a while."
-- Kin Hubbard

Adapted from a real-life case :


GetClient (ClientID);

If client_hair_brown and
client_blue_eyes;
Admit_Client ( ClientID ); // external subprocedure

Endif;


// Admit_Client
GetClient (ClientID);
DoStuff();


Modification : Admit_Client must not be performed if client has long
hair.


Does the modification go in Admit_Client, eg,
// Admit_Client
GetClient (ClientID);
If client_hair_long;
return;
Else;
DoStuff();
Endif;


Or in all the callers?
If client_hair_brown and
client_blue_eyes and
not client_hair_long;
Admit_Client ( ClientID ); // external subprocedure

Endif;





This would mean duplication of code, but putting the modification in
Admit_Client could be misleading to the person reading the caller's
code.