12 Jul
2011
12 Jul
'11
10:46 a.m.
- 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. For example, what is the meaning of
#digit asParser star def: #letter asParser
?
PPUnresolvedParser new def: #letter asParser
has no meaning in the same way your example has no meaning. #def: only
makes sense on a parser instances that are referred to elsewhere (look
at the examples in the tests). Again, there are better ways to do the
same without using the H-bomb of Smalltalk (#def: is a #become:). It
made sense in the beginning of PetitParser, but it is not longer much
useful today.
Lukas
--
Lukas Renggli
www.lukas-renggli.ch