[fpc-devel] Differences between 'tsym' and 'tdef'

[Joost van der Sluis]

Hi all,

I'm trying to implement extended RTTI property attributes as supported
by recent Delphi versions. Extending the parser to allow the property
attributes syntax was easy.

Now I want to add the extended-attribute information to Tpropertysym,
but have to decide how to do that. It is possible to add more then one
such property attribute to one property, so it needs some kind of table.

Now I'm wondering if I should make this new field of Tpropertysym a TDef
or a TSym(table). I know that Tsym can store itself to a ppu while a
TDef does not. But There was something else, too. But I don't remember
exactly. 

So two questions: how should I extend the Tpropertysym for the extended
attributes, and what is the dfference/use of Tdef and Tsym.

I once figured this out for another compiler-patch but I forgot it.

Joost