12 Jul
2011
12 Jul
'11
10 a.m.
On Tue, Jul 12, 2011 at 8:51 AM, Lukas Renggli <renggli(a)gmail.com> wrote:
Because these methods do not refer to self, they could be implemented
in a different class to avoid cluttering the already large PPParser. I
think Kent Beck is talking about that in the Best Practice Patterns
:-)
Sure. But why did you put #def: in PPParser and not directly in
PPUnresolvedParser? For example, what is the meaning of
#digit asParser star def: #letter asParser
?
--
Damien Cassou
http://damiencassou.seasidehosting.st
"Lambdas are relegated to relative obscurity until Java makes them
popular by not having them." James Iry
I guess you are referring to the extension methods in
the package
'PetitAnalyzer'? The methods #matches:, #matchesIn:.
#matchingRangesIn:, ... are part of the core package 'PetitParser' and
are well commented (I think).
The methods in the package 'PetitAnalyzer' are called match*, because
this is not an equality operation. They do not only support the
comparison of two parsers, but can also compare patterns with parser
instances (essentially this is a little Prolog engine, very similar to
the refactoring engine). The matching and rewriting of parsers is
explained in my PhD (http://scg.unibe.ch/archive/phd/renggli-phd.pdf)
in Section "6.2.5 Declarative Grammar Rewriting".
I will have a look, thank you
-
PPParser>>matchList* do never refer to self (but to call themselves
recursively).
This looks correct to me. This is to recurse into the graph of parsers. - Why is #def:
not defined in PPUnresolvedParser? You implemented it
in PPParser. It might be useful for other parsers, but do you have an
example?
PPParser is a superclass of PPUnresolvedParser, therefore you can send
#def: to any instance of PPUnresolvedParser.