Re: [boost] Smart enum

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