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Comment by DCoder | Hacker News Reader

"Takes many types" ≠ "cannot be typed". TypeScript supports decorators, union types, and `any`/`unknown` types.

Those generic use cases are good examples of flexible types, but I have a hard time seeing how

* "I don't know whether the `getMyReplies()` function returns a list of items, an iterator, a non-rewindable generator whose results I need to cache, or a closure with/without memoization" and

* "I don't know whether the singular Reply entity has a field called pid, parent_id, parentId, ParentID, ParentGUID, or parent_message_identifier"

are advantageous to rendering a list of replies.

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For code written in JavaScript you check the source code to see what arguments it takes and what it returns. If it's not written in JavaScript, for example a Browser API's or NodeJS built in module, you read the documentation and use console.log's. Then you rely of good naming, for example (nrA, nrB) => sum vs (a:Number, b:Number) => c:Number where the one without static types is more clear of what the function does and what it returns.

Having to search through source for the argument types of a function is usually an example given in favour of strong typing, not against it.

There are not many reasons to read the code of your dependencies, you will learn a lot doing so. One issue when you work with the compiled code is that the type annotations have been removed, and that type annotations leads to more terse code as it would otherwise become too verbose eg. number:number tends to become n:number and when the type is removed it just becomes n, so you kinda become dependent of your tooling and can't easily just stop using it in favor of something better.

Compiled code doesn't have to be unreadable.

Languages like C and C++ made it readable with debug symbols.

The web stack does the same with source maps. The TypeScript compiler also offers to emit .d.ts files with type information for reuse in other projects.

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