I have a module that represents a configuration file object, say ConfigFile.pm which reads a Configfile.txt file. The overall application is tournament scoring and the ConfigFile contains things like tournament names, various "handicap" values, etc. There are a lot of ways to go wrong when writing the ConfigFile so I have a test/validator program. The output of this test program is not a simple pass/fail module test, but is rather a development tool to inform the user about potential inconsistencies with the purpose of ensuring that the overall program is going to do what the user intends (which may not be what the ConfigFile instructs the program to do!).

Rather than having a separate validator program, I'd like to have the module behave differently when it is executed perl ConfigFile.pm rather than when it is "used", ie: use ConfigFile.pm.

I remember that there is an easy way for the module to know this difference but I have been unable to find this "trick". So my question is how to I do this?

Update:Thanks to Choroba, my code will become: validate() unless caller;

PS: Sorry for long explanation, but I wanted to head off any XY discussion. Yes, this is what I want. validate() is already a method for the object, so I can get rid of an extra .pl file.

Update 2: I thank the Monks for a robust discussion. I've learned at least a couple of things and I thank you all for that.

In reply to Difference between executing and "using" a .pm file by Marshall

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