[fpc-pascal] FPImage and GetDataLineStart

[michael.vancanneyt at wisa.be]

On Fri, 22 Apr 2011, Florian Klämpfl wrote:

> Am 22.04.2011 12:58, schrieb Sven Barth:
>>> No. He can define a record helper operator. The question is simple: do
>>> we want generics behave like macros or more like .Net generics. Some
>>> hybrid approach is imo wrong.
>>
>> Before I forget it: Why do you think that a hybrid approach is wrong?
>
> I meant a semantical hybrid approach, not technical because Users want
> simply rules how things work. So the rule: "only symbols available
> during generic definition time are available during specialization" is a
> simple rule. Every exception like: but operators are available as well
> are hard to understand for a user.

By this rule, the helper class/operator/beast you proposed in the other mail
should also not be available, because it is not known during definition.

Just as a helper is 'attached' to a type, an operator is equally 'attached' 
to the type. Both can be "attached"  by a third party that requires it : 
all that is needed to use it is that it is in your current scope.

To me this means that if you allow the one, you should - logically - allow the other.
(or vice versa)

that this probably presents implementation difficulties, and may require
reworking of operator overloading, I readily believe; I'm just considering
language design at the moment.

Michael.