One reason for processing parameters that "aren't there" is to check that someone isn't modifying a URI in an attempt to break the code?

Yes. At least, that's one way you might legitimately find yourself checking for parameters that aren't there. In that case, however, you are still checking for parameters that you expect to be there. I think there are three good options in that exceptional case:

  1. If you are paranoid about it, then include code that explicitly checks whether the value returned by param() is defined.
  2. If you aren't paranoid about it, then don't write any specific handling for it and let perl spew out some warnings.
  3. If you don't care at all, turn off warnings.

I don't think it is a good practice to write code that simply circumvents warnings which only arise under exceptional conditions. The use of the or-empty construct that started this discussion was just that.

-sauoq
"My two cents aren't worth a dime.";

In reply to Re: Re: Re: Re: Re: Re: Re: "Correct" program style questions by sauoq
in thread "Correct" program style questions by Ovid

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