A
arktype•3w ago
Micha

How to integrate generics with extend that need to access a type in scope?

queryValueObject is currently not resolving, and I assume it's because type() is creating its own scope. The question is, how can I solve it then? 
scope({
  queryValue: [
    "null | string | number | bigint | boolean | queryValueObject | queryValue[]",
    uint8Array,
    dateStub,
    timeStub,
    module,
  ],
  queryValueObject: {
    "[string]": "queryValue",
  },
  namedDocument: {
    read: type("<metadata extends queryValueObject>", { // queryValueObject not resolving
      coll: module,
      name: "string",
      ts: timeStub,
      "data?": "metadata",
    })
  },
}).export();
scope({
  queryValue: [
    "null | string | number | bigint | boolean | queryValueObject | queryValue[]",
    uint8Array,
    dateStub,
    timeStub,
    module,
  ],
  queryValueObject: {
    "[string]": "queryValue",
  },
  namedDocument: {
    read: type("<metadata extends queryValueObject>", { // queryValueObject not resolving
      coll: module,
      name: "string",
      ts: timeStub,
      "data?": "metadata",
    })
  },
}).export();
I also tried it by wrapping it into [], but this does also not work 🤔 
       read: ["<metadata extends queryValueObject>", { 
      coll: module,
      name: "string",
      ts: timeStub,
      "data?": "metadata",
    }]
       read: ["<metadata extends queryValueObject>", { 
      coll: module,
      name: "string",
      ts: timeStub,
      "data?": "metadata",
    }]
10 Replies
ssalbdivad
ssalbdivad•3w ago
Haha luckily there is a much better syntax than that 😛 https://arktype.io/docs/generics#scoped Although the tuple expression thing was a good intuition, because generics are only legal at the top-level of the scope, we can do something more natural with the alias keys themselves
Micha
MichaOP•3w ago
oh, somehow I missed this part in the docs, although I have read over this today probably already 10 times 😬
ssalbdivad
ssalbdivad•3w ago
Admittedly this part of the docs is a bit less elaborate than most of the rest because I consider both scopes and especially generics to be somewhat advanced features, but all the primary syntax is at least covered now!
Micha
MichaOP•3w ago
I've updated it, but I'm still getting an error that metadata is unresolvable Type '"metadata"' is not assignable to type '"'metadata' is unresolvable "'.ts(2322): 
scope({
  queryValue: [
    "null | string | number | bigint | boolean | queryValueObject | queryValue[]",
    uint8Array,
    dateStub,
    timeStub,
    module,
  ],
  queryValueObject: {
    "[string]": "queryValue",
  },
  namedDocument: {
    "read<metadata extends queryValueObject>": {
      coll: module,
      name: "string",
      ts: timeStub,
      "data?": "metadata",
    }
  },
}).export();
scope({
  queryValue: [
    "null | string | number | bigint | boolean | queryValueObject | queryValue[]",
    uint8Array,
    dateStub,
    timeStub,
    module,
  ],
  queryValueObject: {
    "[string]": "queryValue",
  },
  namedDocument: {
    "read<metadata extends queryValueObject>": {
      coll: module,
      name: "string",
      ts: timeStub,
      "data?": "metadata",
    }
  },
}).export();
If I'm renaming "metadata" to "t" the error changes to Type '"t"' is not assignable to type '"true"'.ts(2322) 
"read<t extends queryValueObject>": {
      coll: module,
      name: "string",
      ts: timeStub,
      "data?": "t",
    }
"read<t extends queryValueObject>": {
      coll: module,
      name: "string",
      ts: timeStub,
      "data?": "t",
    }
ssalbdivad
ssalbdivad•3w ago
read is nested in an object there, not at the top-level of the scope
Micha
MichaOP•3w ago
The way you phrase it, sounds like it's a limitation?
ssalbdivad
ssalbdivad•3w ago
Well not really? It wouldn't be sensible to have a generic as the value of a property of an object the same way a Type would be What values would it allow if you used it for validation? But if your goal is to allow namedDocument.read and the . access grouping is important, the way to do that is called submodules: https://arktype.io/docs/scopes#submodules This would prevent it from accessing aliases from the top-level scope though, since it has to be parsed bottom up.
Micha
MichaOP•3w ago
awesome - that is what I need. My goal was to group the types logically to keep it a bit tidy 🙂
ssalbdivad
ssalbdivad•3w ago
Glad you're finding a use case for all the advanced features. Let me know when you run into HKTs 😛
Micha
MichaOP•3w ago
I have to say I'm quite impressed with how far I have already come without a painful workaround (I say only cyclic references + zod... 😉 ). You did here definitely an outstanding job 👍

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