Rescript-compiler: update playground

[bobzhang]

[thangngoc89]

What is this issue about? Could you provide more details?

[bobzhang]

@thangngoc89 this website is not upgraded for a while: https://bucklescript.github.io/bucklescript-playground/

[thangngoc89]

are you ok with me sending a PR upstream changes I've made in nit's playground to bucklescript?

Changes include:

• add refmt_api so playground can support reason syntax out of the box
• support 4.06
• clean up the build process

I can make it several PRs if that's what you prefered

[bobzhang]

@thangngoc89 Yeah, that would be nice.
About changes, small diffs are always preferred, thank you in advance

[ryyppy]

Since #3976 was merged, following playground features are now in:

• Support Reason syntax out of the box
• Add 4.06 support

Here is a list of major tasks we need to tackle next:

External lib loading

• [ ] Make the external lib loading work w/ 4.06 (ReasonReact)
• [ ] Improve the lib loading process by being able to point to different require paths (different React versions etc)

Playground Tests

• [ ] Add simple test infrastructure for the playground bundle
  
  
  
  • [ ] Test: Make sure the bsrefmt / refmt_api versions are in sync!
  
  
  • [ ] Test: Make sure the APIs are correctly exposed
  
  

Scripts and tools

Colocate all important scripts and tools in a toplevel playground directory, also:

• [ ] Copy the cmt / cmj serialization script to the playground dir and fix the serialization problems with the most recent JSOO.
• [ ] Add instructions on how to use the jsoo cli for converting modules into jsoo-serialized js bundles
• [ ] Set repl.js BS_PLAYGROUND to ../playground by default (should always succeed without setting up your own playground directory)
• [ ] Have a single index.html in there loading the exports.js and a simple serve instruction (cd playground && python -m SimpleHttpServer) to quickly test changes manually
• [ ] Redesign the playground API to be more streamlined

Cleanup

• [ ] Get rid of 4.02 based instructions in repl.js / Contributing etc.
• [x] Remove lib/stdlib-402 and all occurrences in the infrastructure?

[ryyppy]

This should be closed in favor of #4450 since things have changed drastically the past few months.