Optional property with const string array

Hello, the following

const x = ["a", "b", "c"] as const;
const myType = type({
  "optional?": type("===", ...x),
});

const x = ["a", "b", "c"] as const;
const myType = type({
  "optional?": type("===", ...x),
});

is giving a

Only required keys may specify default values

Only required keys may specify default values

error. It's not really clear to me why - I assume the === operator is doing more than what I think. Is there a way to have an optional property be one of a string array in arktype? Or is what I'm after effectively indexed access expressions? Thanks

GitHub

Issues · arktypeio/arktype

TypeScript's 1:1 validator, optimized from editor to runtime - Issues · arktypeio/arktype

3 Replies

PIat•4mo ago

What if you do this?

const x = ["a", "b", "c"] as const;
const myType = type({
  "optional?": ["===", ...x],
});

const x = ["a", "b", "c"] as const;
const myType = type({
  "optional?": ["===", ...x],
});

ssalbdivad•4mo ago

Yeah this error is actually just due to a quirk in how some previous versions resolved nested type calls. Updating to the 2.0.0-rc.3 or doing what @PIat suggests will resolve the issue I'd recommend @PIat's suggest as more canonical to avoid nesting type calls where possible Or you can just define the literal union separately then reference it

dibboOP•4mo ago

Oh nice, I didn’t know that was an option. Thank you for the replies

Gaming

Programming

Optional property with const string array