[fpc-devel] class constants

["Vinzent Höfler"]

"Peter Popov" <ppopov99 at gmail.com>:

> PI exists, it has a unique transcedental value, so it should clearly be  
> global. Semanticaly, MyClass1.PI and MyClass2.PI are different  
> identifiers, which given the nature of PI is a ridiculous concept.

The unique transcendental value of PI can not be expressed within a finite computing machine.

So in fact, there may be more than one approximation, i.e. one for single-precision, one for double-precision.

> That is my point: most constants are global in nature. It would be  
> interested to see a class constant which is usefull where a global  
> constant (within a unit) is not.

If the constant is used within the class and in descendants only, it might. I'm a strong believer of reduced visibility.

Of course, as you state, the visibility provided by the unit might be enough. But it also means, that a derived class may need to include that unit whereas in case of a class constant, it wouldn't need to. Not that this is a particularly strong argument. ;)


Vinzent.
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