[fpc-devel] OO rewrite - globals

[Hans-Peter Diettrich]

Florian Klämpfl schrieb:

>> Parser
>> now is derived from the tscannerfile class.
> 
> This is a really ugly design OOP wise ...

When a parser is designed to work with exactly one scanner, why should 
it not inherit from it? In the first approach I added delegates for 
scanner methods to the parser, but since this only adds another level of 
indirection, it has been almost dropped from later versions.


>> Most parser units have been split into .pas and .inc files. The .pas
>> files mostly contain declarations, that can not be moved into the parser
>> unit without causing circular unit references.
> 
> Why don't you use separate parser classes for different purposes?
> Declarations, Function bodies, expressions etc.?

For performance and management reasons, and to prevent cyclic unit 
references. I see no real need for subdividing a grammar into multiple 
(arbitrary) parts. In a future version many syntactical methods can 
become local subroutines, so that they disappear from the methods. The 
suggested separation is much more meaningful for the semantical code, 
i.e. translation into internal data structures etc., up to the final 
code generation.

IOW I see no need to replace CONSUME(whatever) by e.g. 
{self.}base_parser.current_scanner.CONSUME(whatever).

DoDi