Marvin
Marvin
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Aarktype
Created by Marvin on 12/9/2024 in #questions
Framework-level onDeepUndeclaredKey
Hi, thanks for this awesome library! I'm implementing arktype for my team and I plan on using it for DTOs which would validate the input and the output of our tRPC functions. For the output DTOs, I want to enforce the deletion of "deep undeclared keys" to make sure we don't leak any information, like this: 
type({ id: 'string' }).onDeepUndeclaredKey('delete')
type({ id: 'string' }).onDeepUndeclaredKey('delete')
While it works great, I'd like to enforce this at the framework-level, to make sure we never forget to add this onDeepUndeclaredKey('delete'). I thought about doing a dto function wrapper, like this: 
function dto<const def, r = Type<type.infer<def>>>(def: type.validate<def>): r {
  return type<def, r>(def).onDeepUndeclaredKey('delete')
}
function dto<const def, r = Type<type.infer<def>>>(def: type.validate<def>): r {
  return type<def, r>(def).onDeepUndeclaredKey('delete')
}
But I have a Property 'onDeepUndeclaredKey' does not exist on type 'instantiateType<inferDefinition<def, {}, bindThis<def>>, {}>'. error. However, doing dto().onDeepUndeclaredKey('delete') works, for some reason. I could // @ts-expect-error but I'd rather have a clean implementation 😉 Do you have any idea or alternative to achieve what I'm trying to? I think this is a fairly common use-case and a clean solution and docs would be great. Thanks!
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