Optional passing for null?

[m1212e]

Hi, I use a generator to build typebox schemas from my prisma schema. Optional fields from Prisma are returned as value or null. But the typebox typescript type which is derived from the use with Static<> results in a value or undefined. So when I make a DB call I get a type of e.g. string | null for an optional field but the typescript compiler complains because the type derived from the schema which uses Optional() results in string | undefined which is a type mismatch. Can I somehow easily resolve this without having to re map the returned types all the time?

Thanks!

[sinclairzx81]

@m1212e Hi,

So when I make a DB call I get a type of e.g. string | null for an optional field but the typescript compiler complains because the type derived from the schema which uses Optional() results in string | undefined which is a type mismatch. Can I somehow easily resolve this without having to re map the returned types all the time?

Try the following

TypeScript Link Here

import { Type, Static, TSchema } from '@sinclair/typebox'

const Nullable = <T extends TSchema>(schema: T) => Type.Union([Type.Null(), schema])

const T = Type.Object({
   name: Nullable(Type.String()),
   level: Nullable(Type.Number()),
   enabled: Nullable(Type.Boolean())
})

type T = Static<typeof T>

Just keep in mind that Optional means "the property key is optional" (so is somewhat unrelated to null or undefined). The above type has the expectation that all keys must exist, and the property value for each key must be either T | null (as denoted by the union)

Hope this helps
S

[m1212e]

Ah I see. Thank you very much!

[woss]

i think this should be in the readme if it's not already

[louwers]

This should be part of the library I think.

[louwers]

Info here for those wondering: #989