Why doesn’t TypeScript natively do any type checking

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Learning Typescript, I had that same reaction. Others already explained the main reason but there is also another point to it, which I learned while refactoring parts of the runtime type benchmark:

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Yea i guess my question was poorly worded. I understand that validation should not be language level. However, one thing that i would like to see is being able to get the structure of the type at runtime, which i guess would just be a macro. The issue https://github.com/Microsoft/TypeScript/issues/4892 goes over adding macros to the language. The first use case shown there is a validator, which is exactly what i should have asked about in the first place.

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