Re: [gobo-eiffel-develop] Bug in GEC ?

[Wolfgang J. <wj...@so...>]

Howard Thomson wrote:
> Hi Wolfgang and Eric,
>
> According to ETL, the '$' operator applied to a non-constant feature should 
> provide its POINTER address, such that when the pointer is passed to an 
> external routine, that routine can modify the feature, probably returning a 
> previously supplied value.
>
> Unfortunately, EiffelStudio (I think) does not follow ETL and uses, for a 
> reference feature, the '$' operator as an equivalent of SmartEiffel's 
> to_external concept to return the POINTER equivalent of the address of the 
> referred-to object, which is what Eric has implemented to be compatible with 
> ES -- which in my opionion is a pain for both implementations.
>
> Eric will no doubt expound on it.
>
> Just my .0.2c ...
>
> Howard
>
> On Thursday 09 August 2007 15:40, Wolfgang Jansen wrote:
>   
>> Hi Eric,
>>
>> lets consider the program splitter
>>
>>    p1 := $ref_attr
>>    p2 := $int_attr
>>
>> where `p1',`p2' are POINTERS, `ref_attr' is
>> an attribute of a reference type,
>> and `int_attr' is an INTEGER attribute.
>>
>> The effect is that `p2' is set with the address
>> of `int_attr' within `Current'. But `p1' is not
>> set with the address of `ref_attr', instead `p1'
>> is set with the value of `ref_attr' itself.
>>
>> Is this a bug, or did I misunderstand the
>> definition of the `$' operator ?
>>
>> WJ
>>     
>
>   
Thanks for clarifying the point.
So, I will have to live with it.

-- 
Wolfgang Jansen
University of Potsdam, Germany
mailto: wj...@so...