What is the "easiest" way to parse D code?

Given an Expression/Statement/Function/Template.... I want to put it into a program, and it returns me an AST.

D-Scanner seems to do that with `--ast` argument. I would need to dig into it, to get it programmatically, instead of as XML on the stdout.
https://github.com/dlang-community/D-Scanner

libdparse seems to do it as well with `parseModule` function.
https://github.com/dlang-community/libdparse/blob/master/src/dparse/parser.d

dmd has to do it somewhere as well. Although I don't know exactly where. I do know ldc uses dmd's frontend for parsing.
https://dlang.org/phobos/dmd_parse.html


I am also a little confused about who uses what. Does D-Scanner use libdparse?
Is there a D grammar for pegged?
https://github.com/PhilippeSigaud/Pegged

Thank you for any hints!

On Wednesday, 25 November 2020 at 16:27:41 UTC, Jan Hönig wrote:
> What is the "easiest" way to parse D code?
> (...)
> libdparse seems to do it as well with `parseModule` function.
> https://github.com/dlang-community/libdparse/blob/master/src/dparse/parser.d

I recommend libdparse.

> dmd has to do it somewhere as well. Although I don't know exactly where. I do know ldc uses dmd's frontend for parsing.
> https://dlang.org/phobos/dmd_parse.html

DMD as a library is still experimental. You can try to use it, but libdparse is more stable.

> I am also a little confused about who uses what. Does D-Scanner use libdparse?

Yes, most tools that parse D code do, including Adam's documentation generator: https://github.com/adamdruppe/adrdox

Only LDC, GDC and VisualD use the dmd front-end as far as I know.

> Is there a D grammar for pegged?
> https://github.com/PhilippeSigaud/Pegged

Not complete and outdated, but it's a start:
https://github.com/PhilippeSigaud/Pegged/tree/master/examples/dgrammar

On 2020-11-25 17:27, Jan Hönig wrote:

> dmd has to do it somewhere as well. Although I don't know exactly where. I do know ldc uses dmd's frontend for parsing.
> https://dlang.org/phobos/dmd_parse.html

Using DMD as a library will be most accurate and up to date. Because it's the same code as the compiler is using. Here's an example on how to use DMD to parse some code [1]. Here's some more advance usages [2].

[1] https://github.com/dlang/dmd/blob/b35572b07a6994385b6459a430674d32e9a97279/test/dub_package/frontend.d#L10-L24

[2] https://github.com/jacob-carlborg/dlp/blob/master/source/dlp/commands/infer_attributes.d#L61

-- 
/Jacob Carlborg