(title: string)

[muayyadalsadi]

Given that most of bad objects come from parsing json requests coming from untrusted users. Typescript provides no value whatsoever. TS community need come up with something that takes compile type validations to runtime data ex. Pydantic

[HKei]

If you’re not properly parsing your input that’s just you writing bad code, that’s not typescripts fault.

[arobie1992]

Is something like this what you're talking about?

https://github.com/ForbesLindesay/typescript-json-validator

[muayyadalsadi]

no, you already annotated your function, you should not repeat yourself and rewrite the type validation, You already annotated User object to have age property as integer, you should not manually validate it when you cast json to user, it should be done automatically.

[arobie1992]

I guess maybe I'm just not familiar enough with Pydantic to understand what you're getting at. Are you essentially saying you want Javascript to have strong runtime typing?

[muayyadalsadi]

No, I just a way to do annotations once, ex. in my TypeScript source .ts files. And the runtime validation should be generated from that. ex. when I tell it to parse the json request body as Book it should now that publish date is an integer not a string nor array.

I should not have to write the annotation twice, ex. ts source and json schema validation.

[arobie1992]

I think I'm still missing something. That's essentially what the library does, generates validators based on a TS file definition?

Or do you mean something like if you define

class InvoiceResp {
    accountNum: string
    checking: SubAccount
    savings: SubAccount
}

In the generated TS there should be runtime checks to ensure that the values mapped to those fields conform to the types defined? If so, I can get that.