Yes, there are other things like that, that provide error checking on hash keys. There are pseudo-hashes. There's some stuff in Conway's book on OO Perl. There's the use of accessor functions instead of direct hash access. There's Tie::SecureHash mentioned in the 5.8 docs as a replacement for pseudo-hashes for implementing the base/fields modules.

I don't know what does the same kind of type checking you have (as opposed to just allowed keys), but I've read about that kind of thing from time to time.

Perl doesn't require strict typing. In that respect it's more like Smalltalk than C++. That is, an object doesn't necessarily have to be of a particular class (or derived class) to "fit". It just has to have all the right methods available.

In reply to Re: Feedback: Strongly-typed "Pascal records" module by John M. Dlugosz
in thread Feedback: Strongly-typed "Pascal records" module by aspen

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