in reply to Use of "die" in OO modules

Code should fail as early as possible to avoid collateral damage, and to help identify the source of a problem. Using special return values will clutter the code with assertions, which decreases readability and increases the chance that you will miss an exceptional condition.

It is also difficult to come up with a consistent failure convention. Using undef is a bad idea as it is true in list context (any value is), and some functions will return undef as a valid response. -1 is less appropriate. You could bless an error object and return that, but that strikes me as an ugly solution.

I prefer to use Exception::Class, or if I am feeling lazy then die will do. Perl Best Practices has an excellent chapter on Error Handling (13) - I highly recommend it.

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Re^2: Use of "die" in OO modules
by theguvnor (Chaplain) on Jan 18, 2007 at 21:27 UTC

    Thanks for your input, though I should have specified one thing more clearly: when I said I return (undef), I meant that I just return;, I don't return undef;. I'm aware of the problem with returning undef explicitly.

    (For the unaware: a bare return gives the caller an undef, regardless of whether the call was in scalar or list context. Returning an explicit undef gives the caller undef in scalar context and a list containing one element (undef) in list context.)

    [Jon]

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