A
arktype•2mo ago
TheGuy

Is there a good way to use an array of fields mapped from an object into array as string literals?

So probably really simple and I am just missing something. I am trying to achieve the following: 
export const SCOPES = {
  user: {
    can_edit: "can_edit",
  },
  organiser: {
    can_edit: "can_edit",
  },
  event: {
    can_edit: "can_edit",
  }
} as const;

const test = Object.values(SCOPES.user).map((scope) => `'${scope}'`);

export const user = type({
  "...": permissionBase,
  type: "'user'",
  scopes: test
});
export const SCOPES = {
  user: {
    can_edit: "can_edit",
  },
  organiser: {
    can_edit: "can_edit",
  },
  event: {
    can_edit: "can_edit",
  }
} as const;

const test = Object.values(SCOPES.user).map((scope) => `'${scope}'`);

export const user = type({
  "...": permissionBase,
  type: "'user'",
  scopes: test
});
Not sure if this is possible but I may be missing something? The issue obviously comes in that its not a as const. But trying to figure out how I can achieve something like that. In this case its supposed to be an array of those strings.
6 Replies
TheGuy
TheGuyOP•2mo ago
const UserScopes = type(Object.values(SCOPES.user).join(" | ") as `'${typeof SCOPES.user[keyof typeof SCOPES.user]}'`).array();
const UserScopes = type(Object.values(SCOPES.user).join(" | ") as `'${typeof SCOPES.user[keyof typeof SCOPES.user]}'`).array();
^ This seems to resolve type issues The above however seems to give: 'can_edit' is unresolvable
ssalbdivad
ssalbdivad•2mo ago
This is just an issue to do with how narrowly TS is willing to infer Object.values and .map here, not with ArkType specifically. It has to be written or cast such that when you mouse over test, you'd see something that would be a valid ArkType definition You'd need to use some complex types like unionToTuple or a utility function for extracting narrowed values to do this
TheGuy
TheGuyOP•2mo ago
When I moused over it and used it it resolved correctly to what I would expect at type level. Seems to be runtime specific error.
ssalbdivad
ssalbdivad•2mo ago
It should be Object.values(SCOPES.user).map(s => '${s}')join(" | ") Since you want it to be a string literal Or you could use type.enumerated(...Object.values(Scopes.user)) to create the union that way
GreggOD
GreggOD•2mo ago
@CodingWithLuke did this work? We needed this elsewhere in the system. For our other case TS was throwing an error, but runtime worked fine so we just used ts-ignore.
TheGuy
TheGuyOP•2mo ago
Haven't tried the above yet. Could be worth a go I think main issue @GreggOD with my original solution was I had some random spaces in my join. Try my original without that or as per what David suggested.

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