Why would you want to do either of those?

Both are very common Typescript patterns.

Importing without extensions is not a TypeScript thing at all. Node introduced it at the beginning and then stopped when implementing ESM. Being strict is a feature.

What's true is that they "support TS" but require .ts extensions, which was never even allowed until Node added "TS support". That part is insane.

TS only ever accepted .js and officially rejected support for .ts appearing in imports. Then came Node and strong-armed them into it.

Maybe common in some legacy code bases. I recommend running with `erasableSyntaxOnly` for new code bases.

Enums and parameter properties can be enabled with the --experimental-transform-types CLI option.

Not being able to import TypeScript files without including the ts extension is definitely annoying. The rewriteRelativeImportExtensions tsconfig option added in TS 5.7 made it much more bearable though. When you enable that option not only does the TS compiler stop complaining when you specify the '.ts' extension in import statements (just like the allowImportingTsExtensions option has always allowed), but it also rewrites the paths if you compile the files, so that the build artifacts have the correct js extension: https://www.typescriptlang.org/docs/handbook/release-notes/t...

Why not import files with extensions? That's the way JS (and TS) import is actually supposed to work.

I have to admit I was a bit surprised when I was suddenly expected to get rid of all extensions in import. Sure, looks clean, but is it right?