AFIK, there is no such thing as an "immutable object" (an object where the parameters cannot be modified) in Perl. Perhaps there is such a thing in Java or C#. I don't think such a thing exists in C++. Perl is not Java, C# or C++. I guess if you have an object with 'name' as a property when that object was created, just don't expose set_name() in the public interface? If there is no function to change something, and you "play by the rules", then you can't change it. However there are ways in Perl to circumvent any rule and wind up with obscure code that changes a parameter that is not part of the public interface. I think that is also true in C++. My experience with Java is limited and experience with C# non-existent.

I perhaps don't understand your question, but if you want an object which can be created but not modified after its creation... just don't expose any "set" functions for parameters within that object - set all of the params in the "new" method. Nothing in Perl that I know of will prevent you from inheriting from such an object.

I would think that normally your object should have a "has a" relationship to an immutable object rather than your object being an "is a" relationship to said object. Perl will allow you to do something stupid.

In reply to Re^3: Perl OOP by Marshall
in thread Perl OOP by QueenSvetlana

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