Use a grammar parser

[tbarbette]

Recently for ZLT I used Lark (see

npf/npf/expdesign/zltexp.py

Line 18 in 48cb807

constraint_parser = Lark(constraint_grammar, start="start", parser="lalr")

), which is easy and works great.

It should be used for parsing variable as a first step.

Then also to parse the whole .npf file, which would allow to have a clear grammar at the same time.

[Krishn1412]

Hey @tbarbette, can I pick this up?

[tbarbette]

Sure! Thanks :)

[Krishn1412]

Hey @tbarbette, could you please give me some pointers on where to implement the Lark parser for variable. I could not find any parser implementation for variables right now.

[tbarbette]

https://github.com/tbarbette/npf/blob/392bd807679975b767e29b674e1b4c3c46efdb19/npf/models/variables/variable.py#L13C5-L13C19 is the definition of the regex.

All this should be part of a grammar, but the best is to go by step.

[Krishn1412]

Hey @tbarbette, can you take a look at this PR