Typescript

[jorenvandeweyer]

There has been a few times a suggestion to rewrite this library in TypeScript, and even a few times a PR was opened featuring a full rewrite, which we had to decline due to major changes in the code base.

Since @jankapunkt started rewriting the library in ES6+ (#212) instead of ES5 (thank you for that! 🎉 ), I think we finally can start migrating to typescript without major changes to the codebase.

I think we first should decide how our tsconfig should look like before we start writing any code.

I think we can start from this tsconfig.json file

{
  "compilerOptions": {
    "module": "commonjs",
    "target": "ES2021",
    "baseUrl": ".",
    "outDir": "dist",
    "allowJs": true, // This should be changed to false afterwards
    "declaration": true,
    "sourceMap": true,
    "removeComments": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "skipLibCheck": true,
    "strictNullChecks": true,
    "noImplicitAny": false,
  },
  "include": ["lib/**/*", "test/**/*"],
  "exclude": ["node_modules"]
}

[shrihari-prakash]

Hello @jorenvandeweyer ,

I suggest to use also the path attribute so that imports can look very clean and verbose. Something like

"paths": {
      "@grants/*": ["lib/grants/*"],
      "@models/*": ["lib/models/*"],
... and so on....
    }

What do you think?

[jorenvandeweyer]

Yes, good idea.

[jankapunkt]

From my end we can start with this and move to TS step by step. This is also a good way for me to get into TS. One note - we should keep the documentation examples in JS to stay as inclusive as possible.

[binajmen]

Don't ask me how I ended up here, but my 2 cents on the subject would be to consider JSDoc instead.

TypeScript is great for application development, and it's getting better all the time. But for library development, JSDoc annotations in plain JavaScript seems like the way to go.

A library like Svelte decided to drop TS in favour of JSDoc. You still keep type checking (+ all the perks like documentation, etc.), plus it allows you to do things incrementally.

Just some food for thought ;)