Re: How to say 'oops' in OOPs?

I would say that a lot depends on how OO your system is.

A completely OO system would tend towards throwing and catching Error objects. Perl5 doesn't explicitly support this (but it can be done - q.v. Error for one way to do it).

If you're using objects to encapsulate logic within a procedural system, I would go ahead and do something like what DBI does - return undef to indicate failure and set an error string method (called errstr in DBI). However, this requires a consistent API across all of your objects (because you don't want some doing one thing and others doing another).

The procedural way to do it (like C) is to return 0 on success and some number on failure, that number being used to look up some error string. (This is also similar to the way eval uses $@.)

Pick your poison, I guess.

Update: As per Abigail-II, I stand corrected.

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Comment on Re: How to say 'oops' in OOPs?

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Re: How to say 'oops' in OOPs? by Abigail-II (Bishop) on Apr 08, 2003 at 14:55 UTC
Actually, C tends to return `-1` on failure, setting `errno`. For functions returning pointers, a `NULL` return value is often used to indicate failure. Abigail	[reply] [d/l] [select]
Re^2: How to say 'oops' in OOPs? by adrianh (Chancellor) on Apr 09, 2003 at 10:46 UTC
I would say that a lot depends on how OO your system is. Exception throwing vs. returning error values is a separate issue from whether your system is OO or not. You can have non-OO systems that throw exceptions. You can have OO systems that return error objects.	[reply]