Standard library status

[davesnx]

The current Js and Belt are compatible with the ones shipped with rescript and those contain a few issues from the past 1 2 and a few issues from the present 1 2 (Those aren't necessary issues directly, but to showcase that most people spend time re-working the stdlib).

Without getting myself into a lot of troubles, we could work-out a bit the status of those modules considering:

• Records are represented as JavaScript Objects.
• Exceptions won't have the shape and we might be able to solve compatibility with JavaScript errors.
• Pipe-first plays really well with labelled arguments while pipe-last plays very well without labelled arguments (and we have some examples of that: https://github.com/darklang/tablecloth-rescript)
• We might want to cross-compile (or virtualise) them.
• First versions of Melange will remain compatible but eventually we can forge it and evolve them freely.

Opening this issue to gather information/opinions on what's a good idea and what's a bad idea.

[anmonteiro]

I'm open to ideas and contributions on this. However:

• let's discuss each separate small change in isolation -- this is the stdlib after all and we need to be really mindful about changing it
• expect some bikeshedding, and some ideas that won't be able to make it in

[davesnx]

Totally, this issue is to discuss the bikeshedding and how to move forward. I'm currently doing a lot of work on this but happy to adapt/change anything.

I personally don't have much opinion about those topics, so anyone is more appropriate than me to drive this.

[texastoland]

Re. #731