Interactive mode for prqlc

[vanillajonathan]

prqlc could have a interactive mode though an -i or --interactive option.

Example:

$ prqlc --interactive
prqlc 0.9.3
Type '?' for help.

In [1:] from invoices
   ...: filter income > 5
   ...: sort {-sum_income}
   ...: take 20
   ...: 
SELECT
  *
FROM
  invoices
WHERE
  income > 5
ORDER BY
  sum_income DESC
LIMIT
  20

In [2:]

[eitsupi]

Wouldn't it be better to create another tool rather than making prqlc bigger?

[vanillajonathan]

Good point. It could be called iprql like ipython.

[max-sixty]

I think this is a great idea, and I was thinking of doing something like this at one point — maybe more like a TUI with two panes, like the playground.

There could be shortcut keys for copying to clipboard, for viewing intermediate compiler outputs, etc.

The main reason not to do it is that we already have the playground & VS Code. But the playground takes ~30s to start on local code each time. And VS Code works best when saving a .prql file, rather than just typing an example.

[vanillajonathan]

I was thinking something more REPL like ipython. Not a two-pane TUI like the playground.

[max-sixty]

What's the advantage of a REPL? I haven't thought about it that much, but seems like two main differences:

• The two-pane layout gives an instant result, vs. REPL gives a result on every evaluation
• The two-pane layout's state is completely defined by what's currently in the document; there's no history. A REPL has variables that can be created / overwritten. (which I think is also worse, though maybe folks have other preferences?)

[vanillajonathan]

Good point. Maybe a two-pane TUI would be a better fit for PRQL. When I made this post I got the idea from ipython.

[snth]

Didn't the original pyprql TUI do some of this?

[max-sixty]

Yes it did! It was great for this!

[snth]

So to some extent prqlc already does this:

❯ prqlc compile | duckdb
Enter PRQL, then press ctrl-d to compile:

from [{greet="hello @vanillajonathon"}]
┌────────────────────────┐
│         greet          │
│        varchar         │
├────────────────────────┤
│ hello @vanillajonathon │
└────────────────────────┘

However you don't get much interactivity beyond what's offered by your shell. IIRC there are readline wrappers that might give you basic functionality with 5 minutes of work. Something like https://github.com/hanslub42/rlwrap.

Otherwise using some of the https://charm.sh/ tools?

[snth]

This is very much in my wheelhouse and I have big plans to build something along these lines but I can't promise anything at this stage since I'm unlikely to keep any such promise.