Comment by teaearlgraycold
6 months ago
That is an issue with how TS works, but it can be significantly improved upon by using a library to verify the structure of deserialized data. zod is one example, or you could use protobufs. Fundamentally, this is an issue with any programming language. But having your base "struct"-like type be a hashmap leads to more mistakes as it will accept any keys and any values.
I disagree that this is an issue in every language - the problem is that in other languages the validation against some schema is more or less required for unmarshalling, and it's optional in TS.
Seeing a deserialization error immediately clues you in that your borders are not safe. Contrast that with TypeScript, where this kind of issue can lead to an insidious downstream runtime issue that might seem completely unrelated. This second scenario is very rare in other languages.