[Lazarus] Forward declaration not solved

Marcos Douglas md at delfire.net
Fri Aug 9 22:00:06 CEST 2013

On Fri, Aug 9, 2013 at 3:13 PM, Santiago Amposta <svaa at ciberpiula.net> wrote:
> El 09/08/2013 11:15, Antonio Fortuny escribió:
>> But the isn't there some ambiguity between LCL declarations and FPC
>> declarations for what is obviously the same type ?
>> Thanks Mattias,
> In delphi, exists sysutils.abort and windows.abort. I don't know how
> long it took me to find the bug: Just because "windows" was used after
> "sysutils". In this case the compiler didn't complain, and the errors
> where very weird.
> Other languages, like Ada, raise a compiler error.  IMHO, the FPC should
> not allow such ambiguity and raise an error, asking to qualify the
> identifier. I suppose it would break backward compatibility, a directive
> {$Check_Ambiguity+} would be fine for me ;-)


> When you work with big programs, you are going to face with identifier
> collisions.  The solution is not to change identifier, probably each
> unit programmer chose such name for good reasons,  but using namespaces,
> that object pascal already has. The current solution, relying in the
> order of units to guess which one will pick, is a prone of errors, and
> sometimes very difficult to find, because most of us aren't aware of
> this most time, and don't code with this concept in mind. With hundreds
> of third party libraries and components, I am sure many people have hit
> this error and gone nuts for a while.
> The reason why things like this don't happen more often is because units
> usually contain objects and we use things encapsulated in object more
> often than global identifiers. But that is not an excuse, relying in
> "uses" order is a poor decision from old times that could be improved.
> Sure it's a FPC topic, but I couldn't help... it's just a rant ;-)

Namespaces was discussed many times on FPC list and many ideas were
said, however no idea was good enough for FPC team, unfortunately.

Marcos Douglas

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