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From: Tobias Schwinger (tschwinger_at_[hidden])
Date: 2006-04-01 15:22:23


Andy Little wrote:
> "Tobias Schwinger" wrote
>
>
>>// IS_TYPE((int))::value is true
>>// IS_TYPE((1))::value is false
>>
>>Does anyone know how to implement this without a typeof operator?
>
>
> I havent got a solution but one avenue thats seems to be in the right field is
> to exploit the difference between a function call and a declaration:
>
> Sometype func_or_value( Entity_to_test);
>
> eg assume Entity_to_test is a type then func_or_value is a function, else
> func_or_value is a variable.
>

Yeah, this route occured to me. Unfortunately it requires namespace or class scope to work, while the typeof version can be encoded in a single expression.

> Dont know if it helps though. The other slim hope is exploiting how e.g
> std::for_each uses its last argument, but I dont quite know how that would help
> if at all.

I'm not sure I know what you mean. Would you elaborate?

Regards,

Tobias


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