Posts tagged PEG
QuickNote: Arpeggio
- 2022/11/08
In this short QuickNote, we give a bit of info on Arpeggio; a python package to implement a (PEG) parser. Eventually, the parser is written in Castle – like all Workshop Tools. To kickstart, we use python and python-packages. Where arpeggio is one of the options.
As Arpeggio is quite well documented this is a short note. We also describe some differences with the Pegen package.
QuickNote: PEGEN
- 2022/11/03
To implement CCastle we need a parser, as part of the compiler. Eventually, that parser will be written in Castle. For now, we kickstart it in python; which has several packages that can assist us. As we like to use a PEG one, there are a few options. Arpeggio is well known, and has some nice options – but can’t handle left recursion – like most PEG-parsers.
Recently python itself uses a PEG parser, that supports left recursion (which is a recent development). That parser is also available as a package: pegen; but hardly documented.
Grammar is code
- 2022/05/14
In Compiler Compiler we have seen that we can define a grammar within a Castle-program. And we have argued that each grammars-rule can be considered as a function.
In this post, we look into de details of how this works. And will confirm grammars is code …