Re: Type safety, C++ and code generation

[Maciej Sobczak <no.spam@no.spam.com>]

Martin Krischik wrote:

>>What about making different types really distinct?
>>
>>typedef ranged_type<int, 0, 100> R1;
>>typedef ranged_type<int, 0, 100> R2;
>>typedef ranged_type<int, 0, 101> R3;
>>
>>
>>Above, R1 and R2 are equal to the compiler

> This is because "typdef" in C++ is "subtype" in Ada.

Not really - you cannot add constraints with typedef. ;)

> You would need:
> 
> class R1 : ranged_type<int, 0, 100> {};
> class R2 : ranged_type<int, 0, 100> {};
> class R3 : ranged_type<int, 0, 101> {};
> 
> to create new types.

Except that those new types would be problematic to use with operations 
that are already defined for ranged_type (especially those which return 
ranged_type), because there is no implicit conversion to the derived class.


-- 
Maciej Sobczak : http://www.msobczak.com/
Programming    : http://www.msobczak.com/prog/