Hi,

I think it was FPC 2.6.0 that changed the language rules about Properties. You can't pass them directly as a var parameter, can't assign to a property of a property etc.

Anyway, somebody recently asked my why this was implemented, and I can't actually remember the exact rational behind the FPC team's decision.

Does anybody have a link to the documentation or FPC discussion on this? I'm looking for info on what was so bad about the old behaviour etc. and if this was another Delphi compatibility change or not?

I want to pass this information on, but want to make sure I get it right.

Regards,
- Graeme -

On Sun, June 8, 2014 21:50, Graeme Geldenhuys wrote:

Hi Graeme,

Have you already checked the "User changes 2.x.0" pages of the respective releases (especially
http://wiki.freepascal.org/User_Changes_2.6.0#Taking_the_address_of_fields_of_record_properties and
http://wiki.freepascal.org/User_Changes_2.4.0#Treating_direct-mapped_properties_as_regular_fields referenced from the previous one)?

Tomas

2014-06-08 21:50 GMT+02:00 Graeme Geldenhuys
:

See reason:
http://wiki.freepascal.org/User_Changes_2.4.0#Treating_direct-mapped_properties_as_regular_fields

Vincent

Graeme Geldenhuys wrote

You can't pass them directly as a var parameter,

I feel that generally passing a property as a var parameter is not possible,

It could be possible for built-in functions (such as inc() ) or for properties that don't have a set or get function.

Of course the compiler could detect these special cases. I don't know if it does make sense to handle them.

-Michael

possible,

It could be possible for built-in functions (such as inc() ) or for

properties that don't have a set or get function.

Of course the compiler could detect these special cases. I don't know if

it does make sense to handle them.

If you would look at the wiki articles linked by others already which describe the changes and the reasoning behind them you'd know why we don't allow properties to be passed to var parameters anymore.

Regards,
Sven