> Micha Nelissen wrote: >> <code> >> type >> TGenericCollection = generic(T: TCollectionItem) class(TComponent) >> ...implement TCollection and use T >> end; >> >> TCollection = TGenericCollection of (TCollectionItem); >> TFieldDefs = TGenericCollection of (TFieldDef); >> </code> > > So generic procs could look like: > > <code> > function generic(T: TTreeItem) MyFunc(A: T): T; > begin > // do something with the tree item > end; > </code> > > My restrictions won't allow implementing generic Max and Min, I guess. > That really needs macro-alike stuff (for the compiler implementation). > The syntax could look like: > > <code> > function generic(T) Max(A, B: T): T; > begin > if A < B then > Result := B > else > Result := A; > end; > </code>
I did some tests with g++. It looks like it parses the template 'normally' and don't handle it like a macro. When instantiating the template the generic type is replaced. I don't know if that is possible with FPC. The parser relies a lot on types being available. Writing a special parser for generics is possible. It can then store a simple expression/statement tree that will generate a full node tree when the generic is instantiated. But that means that it must be known that _______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
