Le 03/05/2015 10:42, Julien Delplanque a écrit :
Hi everyone,
I saw on this repository https://github.com/antlr/grammars-v4 that there are a lot of grammar defined. I wonder if someone already managed to generate a parser in pharo (using any framework you want) from a ".g4" file?
Not me, even if I have spent time pouring over ANTLR-based grammars when implementing compiler front-ends. ANTLR-based grammars are LL* (right recursive), so they don't fit very well with LALR/GLR (SmaCC), they tend to look a bit different from the programming language official doc or standard (i.e left-recursive), they are in some cases difficult to reuse because resolution may be done in ad-hoc fashion (adding arbitrary code to resolve ambiguities), and whether the grammar is really complete for a given language is hard to determine (working grammars for real-life complete uses are expensive to build, so they tend to be kept as company Intellectual Property). This is my experience.
I also saw there is the grammar of ".g4" files (https://github.com/antlr/grammars-v4/tree/master/antlr4) in the repository so I guess it would be possible to create a parser that generate parsers from ".g4" files.
This is correct. Thierry
Regards,
Julien