esm only and deprecate cjs build

[ryoppippi]

Today, js is becoming esm first: esm works in browsers and has advantages for tree-shaking.
So we want to replace the parts of various scripts where commonjs are used with esm. We still intend to include commonjs in the build.
I'll work on it if you want.

[samchon]

The transformer (typia/lib/transform) must keep the CJS because tsc is using it.

Also, typia must be both CJS and ESM compatible, due to main purpose of typia is supporting nestia, especially for A.I. chatbot.

• https://nestia.io/docs/swagger/chat/

If you can keep two things without break change which requires major version update, it is okay to start.

[ryoppippi]

@samchon okay got is
we must include cjs, for transformer for sure.

[samchon]

Also, keep the CLI (npx typia setup) command as CJS please.

It is imported by nestia and the nestia's basic library NestJS is still using CJS too.

[ryoppippi]

Nice! got it!
Actually, I keep all cjs build, but the primary script will be esm

BTW, in the future we can deprecate CJS because of this flag https://nodejs.org/en/blog/announcements/v22-release-announce#support-requireing-synchronous-esm-graphs

[samchon]

I'll deprecate CJS when TypeScript and NestJS do it.

[ryoppippi]

https://antfu.me/posts/move-on-to-esm-only
FYI

Actually I already finished moving to ESM first. I'll investigate whether test works fine.

[ryoppippi]

require(esm) in node20 is supported now
reaches end-of-life (EOL) in April 2025, so now we can get rid of commonjs.
nodejs/node#56927

[ryoppippi]

@samchon
So now we can use Nestjs with esm, we can go to esm only I think

https://blog.arcjet.com/nodejs-22-support-esm-require-for-nestjs/

Also we can only support the latest 22 & 20 nodejs in v8.

[ryoppippi]

@samchon
I experimented that we can use es module with nest.js with the latest node 20 and 22

Frankly, I don't think we should be stuck with old writing systems like CJS and namespace forever.

It is also difficult to maintain both CJS and ESM. esm runs as is in the browser and has a smaller bundle size. Scripts can also use top-level await.
Clearly, continuing to support cjs or writing scripts in cjs is an anachronism (the same can be said for other projects)

[ryoppippi]

I'll work on it, but at first please read this if you have time (maybe after April?)
https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c