Script-defined compiler options

[vanillajonathan]

What if the script could define compiler options?

Example:

prql.signature_comment = false
prql.sql.format_style = "river"
prql.sql.lowercase = true
prql.sql.use_brackets = true

from tracks
select {artist, title}
sort title

Output:

  select [artist], [title]
    from [tracks]
order by [title]

[max-sixty]

Yes, we could offer more options in the header, like signature_comment: https://prql-lang.org/book/project/target.html

[eitsupi]

This reminds me, it would be great to be able to write prql header on multiple lines.

[max-sixty]

Do you think the new line wrapping is sufficient?

[eitsupi]

Do you think the new line wrapping is sufficient?

I think so. Does this already work?

[max-sixty]

I just tried and I think so! This correctly fails with a header specifying a newer version than the current compiler:

echo 'prql
   \ version:"0.10.0"

   from tracks' | cargo run -p prqlc -- compile
   
    Finished dev [unoptimized + debuginfo] target(s) in 0.10s
     Running `target/debug/prqlc compile`
Error: This query uses a version of PRQL that is not supported by the prql-compiler. Please upgrade the compiler.

[eitsupi]

That's great! Thanks for trying.

[snth]

I think this is a good idea. I am in support of it to the extent of exposing any options that sqlformat provides. I don't think we should be spending our time formatting SQL code since that's for machine consumption (since we're all writing PRQL right 😉).

---

I hadn't heard of the "River" formatting style for SQL before but found this: Modern SQL Style Guide

I like it! Thanks @vanillajonathan .

I would like to explore supporting River formatting for PRQL code!

[snth]

I believe we currently use the sqlformat crate for SQL formatting so the available options would be found here: https://docs.rs/sqlformat/latest/sqlformat/struct.FormatOptions.html

[snth]

That Modern SQL Style Guide also has an interesting bit on bracket-escaping table and column names. It's something I've been thinking about for a while and I'll write up in a separate discussion.

[max-sixty]

(I do think our options are somewhat limited on SQL formatting specifically, so discussing various formatting options has fairly low returns unless there's some willingness to make a fairly large contribution upstream)

[vanillajonathan]

I came across the "river style" formatting in the SQL Style Guide by Simon Holywell.