WARNING: it won't be simple I'm using visitor pattern in my project and to the best of my knowledge, the visitor should be implemented as an interface. After everything goes compiled, I found out a weird behavior. That is, all the change during accept-visit is gone after control goes back to the initiator (first accept). Even worse, I can't free the object! It causes access violation.
I attach the project that shows this. The project is quite big, but you can focus to only two units (more precisely, to their interface as seen in the attached diff): ast and cg. I create two versions of both units (the other using class with abstract methods) and their diff is attached. Try compiling with both versions (by renaming the one you want to compile to the right name, e.g. without .tmp suffix). Ensure linguc.lpr on line 118 is commented when you're using the interface version (it causes access violation as I state above). Attachment: http://free-pascal-general.1045716.n5.nabble.com/file/n3353651/intf.zip intf.zip -- View this message in context: http://free-pascal-general.1045716.n5.nabble.com/Weird-interface-behavior-tp3353651p3353651.html Sent from the Free Pascal - General mailing list archive at Nabble.com. _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
