TypeScript Compiler & ReasonScript Interop

This project tries to setup interaction between the TypeScript and the Reason compiler. We use genType to generate TS type declarations from ReScript.

Getting Started

Installation

npm install

Native:

opam switch create 4.11.1
opam install base stdio dune ocaml-lsp-server atdgen

Building

npm run re:build && npm run build

Native build:

dune build src/ocaml/read_ast.exe

Continuous Build

npm run re:watch

In another:

npm run watch

Running

npm run run src/examples/tree.ts

Run native:

_build/default/src/ocaml/read_ast.exe src/examples/tree.ts.json

Implementation Notes

atd

The data types and JSON (de-)serializers for asts are generated by atdgen. To re-generate, run:

npm run atd

Usage Notes

I have not yet figured how to let this multi-project setup play nicely with Merlin. If one deletes the .merlin file at the root, then it works nicely for all the OCaml files. Otherwise, it will not find the local libraries. However, the .merlin file is probably needed to get all features for ReScript files.

Setup Notes

• genType only generates .tsx files (issue). We work around this by setting "jsx": "react" in tsconfig.json.
• genType uses require (issue). This is annoying because it means we cannot use Node's ES6 module mode. Workaround: use the esm package.
• In Node's ES6 mode, file paths need to carry explicit file type suffixes. TS refuses to generate them. One way to fix it is to use .js imports in the original TS file (like so). The other is to update tsconfig like so. This problem vanishes as soon as we use esm.
• The paths to the Babel plugins in src are set as absolute paths in babel.config.json, and need to be adopted to your machine. They should go after all official Babel plugins, in the following order:
  • mybabel
  • babel-for-to-while
  • babel-transform-update-expression
  • babel-transform-object-spread
  • babel-transform-unary-expression
  • babel-transform-delete
  • babel-transform-array-push
  • babel-transform-property-assignment
  • babel-rename
  • babel-hoist-declarations
  • babel-transform-internals
• The module simple_fun needs to be installed locally via opam.