Re: Call for Google Summer of Code 2021 project ideas

[John Snow <jsnow@redhat.com>]

On 2/15/21 6:05 AM, Paolo Bonzini wrote:
> On 14/01/21 17:36, John Snow wrote:
>>
>>> The sane way to evade the language design problem is to use the existing
>>> QMP language.
>>
>> I wouldn't mind implementing this for version 0.1 -- just allow 
>> copy-pasting JSON into the input bar -- it's a feature I wanted anyway.
> 
> I think the only way out of language design is to instead design a TUI 
> for inputting JSON.  For example:
>  > * after typing the ' for a key you can autocomplete the next field,
> using the TAB key similar to vi
> 
> * after typing the : the TUI tells you the field type
> 
> * after typing the ' for an enum, the TAB brings up a menu to pick an enum
> 
> * after typing the last character in a key or value you automatically 
> get a suggestion for what to type next (comma and next apostrophe after 
> a value, colon and possible apostrophe/bracket/brace for a key)
> 
> One idea that has worked for me in the past was to write a mockup that 
> shows what things are going to look like, with fake user interaction. 
> You would have something like
> 
>     // {
>     keypress("{")
>     show_suggestion("'")
>     // '
>     keypress("'")
>     start_autocomplete_choices(["execute", "arguments"])
>     // TAB
>     await asyncio.sleep(1)
>     do_autocomplete()
>     // '
>     await asyncio.sleep(1)
>     keypress("'")
>     // string argument, propose ' for the value automatically
>     show_suggestion(": '")
>     // TAB
>     await asyncio.sleep(1)
>     do_autocomplete()
>     start_autocomplete_choices("query-status", "query-kvm") # many more
> 
> etc.
> 
> Then you plug in an incremental lexer, so that you can e.g. replace
> 
>     show_autocomplete(": '")
> 
> with
> 
>     lex_state(Lexer.AFTER_KEY); // this would come from the lexer
>     show_autocomplete("'")      // this would come from the schema
> 
> And then again plug the incremental visitor to autocomplete on the 
> schema types.
> 
> Another advantage of this approach is that you also have a natural API 
> for the mocks, and thus it becomes easier to write testcases.
> 
> Paolo
> 

Yes, I follow.

I quite like the VSCode auto-suggest behavior for writing JSON when you 
have a schema, but that's baked into their borg-cube, I assume.

I wonder if there's any libraries or more re-usable pieces out there 
that would allow us to write a nice interactive TUI for complex 
structures in Python, or if we'd have to design and build it ground-up.

Changes how willing I am to embark upon the quest.

--js