Hi,

On 27 Jul 2010, at 12:02, Alberto Bacchelli wrote:

Hi,

In order to define a Java grammar in PetitParser, I am looking at how PetitSmalltalk is implemented.

• Should a grammar like that of a programming language be

created as a subclass of PPCompositeParser? What's the advantage over just a subclass of PPParser?

It offers a nice infrastructure to define the productions as methods and reference them through instance variables.

Take the following example:

PPArithmeticParser>>terms ^ addition / factors

terms is a production that is defined in terms of two other productions: addition and factors. These two productions are actually instance variables in the PPArithmeticParser class and have corresponding methods defining the productions. For example:

factors ^ multiplication / power

Cheers, Doru

• Unfortunately, I do not understand why PetitSmalltalk uses a

PPSmalltalkTokenParser instead of a normal "token".

The comment of PPSmalltalkTokenParser says: A parser that knows how to skip comments and whitespace in Smalltalk and how to instantiate tokens.

Cheers, Doru

Thanks, Alberto _______________________________________________ Moose-dev mailing list Moose-dev@iam.unibe.ch https://www.iam.unibe.ch/mailman/listinfo/moose-dev

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