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

[Howard T. <how...@di...>]

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

-- 
Howard Thomson

--
"Only two things are infinite, the universe and human stupidity,
and I'm not sure about the former." -- Albert Einstein