The solutions from huck and 1nickt look fine to me. Note: BrowserUk's idea about require is also applicable to this problem.

I don't know whether you need the flexibility of different algorithms between states or just different parameter values, like "state sales tax" or whatever.

A different approach to consider might be the SQLite DB. This DB uses a simple file instead of a separate SQL server process. It works very well (I think every smartphone has a SQlite DB). The Perl DBI for SQLite is excellent and I've used it on a number of projects; some small and some with millions of records. Your module could access the DB to get values for whatever state you tell it you are in.

Also one point to consider is maintenance. In general maintaining a single US DB is probably easier than 50 different state specific modules expressed as Perl code. I know very little of your actual application. If this sounds like it is worth pursuing for you, happy to provide more information and suggestions.

Update:
Another try at an explanation: If you can express the functions for each state as a single set of "code" with 50 different sets of "data", I would recommend the DB approach even if this complicates the code logic in this "single set" of code. If you have 50 different sets of code, that can vastly complicate the maintenance.

What you apparently want to do may adopt itself well to an OO paradigm. The user program says: "use StateFormulas;". When creating a new StateFormula object, specify the state. When the object is created, data is read from the DB. This object for say TX (Texas) now works differently than one for say IA (Iowa) because of differing parameters. If say the Texas calculations are somehow different because it has a coastline, then I would put a field in the DB like "has_coastline". The code will perhaps wind up some "if" statement, but that if statement will apply to all states with a coastline. If you go this way then code could wind up with easy comparisons between different states because each object in the program would be specific to a state rather than saying "hey now this program works specifically for TX". Hope this helps.

In reply to Re: Imagination greater than reality? by Marshall
in thread Imagination greater than reality? by writch

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