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Micha

•Created by Micha on 2/5/2025 in #questions

Why is the generic expecting 3 options, although there is only one generic prop?

import { type, scope } from "arktype";

const types = scope({
  queryValue: "null | string | number | bigint | boolean",
  queryValueObject: {
    "[string]": "queryValue",
  },

  "namedDocument<metadata extends queryValueObject = Record<string, never>>": { // namedDocument has only one generic "metadata"
    "data?": "metadata",
  },
}).export();

// this requires 3 options, but I would expect only 1 (metadata)
const namedDocument = types.namedDocument("object", "object", "object")

import { type, scope } from "arktype";

const types = scope({
  queryValue: "null | string | number | bigint | boolean",
  queryValueObject: {
    "[string]": "queryValue",
  },

  "namedDocument<metadata extends queryValueObject = Record<string, never>>": { // namedDocument has only one generic "metadata"
    "data?": "metadata",
  },
}).export();

// this requires 3 options, but I would expect only 1 (metadata)
const namedDocument = types.namedDocument("object", "object", "object")

If I remove extends queryValueObject = Record<string, never> I only need 1 options. If I remove extends queryValueObject, it goes up to 4 options. And if I remove only = Record<string, never>, it also goes down to 1 required option.

5 replies

Aarktype

•Created by Micha on 2/4/2025 in #questions

scope() how to bypass circular reference error?

I've implemented with Scope() successfully circular references, but somehow, I hit a limitation as this one still throws a circular reference error:

const types = scope({
  queryValue: "namedDocument", // As soon as I add here namedDocument the error appears
  queryValueObject: {
    "[string]": "queryValue",
  },

  "namedDocument<metadata extends queryValueObject = Record<string, never>>": {
    "data?": "metadata",
  }
}).export();

const types = scope({
  queryValue: "namedDocument", // As soon as I add here namedDocument the error appears
  queryValueObject: {
    "[string]": "queryValue",
  },

  "namedDocument<metadata extends queryValueObject = Record<string, never>>": {
    "data?": "metadata",
  }
}).export();

Error:

Type of property 'namedDocument' circularly references itself in mapped type '{ [k in "namedDocument<metadata extends queryValueObject>" as extractGenericName<k>]: GenericAst<conform<parseNextNameChar<skipWhitespace<extractParams<extractGenericParameters<k>>>, "", [], bootstrapAliases<...>>, array<...>>, { ...; }[k], "$", "$">; }'.ts(2615)

Type of property 'namedDocument' circularly references itself in mapped type '{ [k in "namedDocument<metadata extends queryValueObject>" as extractGenericName<k>]: GenericAst<conform<parseNextNameChar<skipWhitespace<extractParams<extractGenericParameters<k>>>, "", [], bootstrapAliases<...>>, array<...>>, { ...; }[k], "$", "$">; }'.ts(2615)

14 replies

Aarktype

•Created by Micha on 2/4/2025 in #questions

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",
    }]

15 replies

Aarktype

•Created by Micha on 2/4/2025 in #questions

How to create the Typescript type from a generic?

https://arktype.io/docs/generics

const document = type({
  id: "string",
  coll: type.instanceOf(Module),
  ts: TimeStub as type.cast<TimeStub>,
  "ttl?": TimeStub as type.cast<TimeStub>,
});

const namedDocument = type("<t>",["t", "&",{
  coll: type.instanceOf(Module),
  name: "string",
  ts: TimeStub as type.cast<TimeStub>,
  "data?": "object",
}]);

const test = namedDocument(document) // This works as expected

type Document = typeof document;
type NamedDocument = typeof namedDocument;
const test: NamedDocument<Function> // This  throws the error Type 'NamedDocument' is not generic.ts(2315)

const document = type({
  id: "string",
  coll: type.instanceOf(Module),
  ts: TimeStub as type.cast<TimeStub>,
  "ttl?": TimeStub as type.cast<TimeStub>,
});

const namedDocument = type("<t>",["t", "&",{
  coll: type.instanceOf(Module),
  name: "string",
  ts: TimeStub as type.cast<TimeStub>,
  "data?": "object",
}]);

const test = namedDocument(document) // This works as expected

type Document = typeof document;
type NamedDocument = typeof namedDocument;
const test: NamedDocument<Function> // This  throws the error Type 'NamedDocument' is not generic.ts(2315)

7 replies

Aarktype

•Created by Micha on 2/3/2025 in #questions

Is there a way to preserve jsdoc in arktype?

I have this piece of code:

/**
 * Defines a {@link https://docs.fauna.com/fauna/current/learn/security/roles/#user-defined-role | user-defined role}. A role determines an authentication secret’s privileges, which control data access.
 *
 * Fauna stores user-defined roles as documents in the `Role` system collection. See {@link https://docs.fauna.com/fauna/current/reference/fql-api/auth/role/ | Role}.
 */
const role = type({
    /**
     * Assigns the role to tokens based on the {@link https://docs.fauna.com/fauna/current/learn/security/tokens/ | token’s} identity document. See for more information on {@link https://fauna.com/docs/reference/javascript#membership-roles | Membership definition}.
     */
    "membership?": "string",
    /**
     * Allows one or more actions on a resource. See {@link https://docs.fauna.com/fauna/current/reference/fsl/role/#privileges-definition | Privileges definition}.
     */
    "privileges?": "string",
});

export type Role = typeof role;

/**
 * Defines a {@link https://docs.fauna.com/fauna/current/learn/security/roles/#user-defined-role | user-defined role}. A role determines an authentication secret’s privileges, which control data access.
 *
 * Fauna stores user-defined roles as documents in the `Role` system collection. See {@link https://docs.fauna.com/fauna/current/reference/fql-api/auth/role/ | Role}.
 */
const role = type({
    /**
     * Assigns the role to tokens based on the {@link https://docs.fauna.com/fauna/current/learn/security/tokens/ | token’s} identity document. See for more information on {@link https://fauna.com/docs/reference/javascript#membership-roles | Membership definition}.
     */
    "membership?": "string",
    /**
     * Allows one or more actions on a resource. See {@link https://docs.fauna.com/fauna/current/reference/fsl/role/#privileges-definition | Privileges definition}.
     */
    "privileges?": "string",
});

export type Role = typeof role;

At the moment the TS type Role don't have JsDoc as part of Intellisense. Also, role has only the overall jsdoc, but not for the key membership & privileges

2 replies

Aarktype

•Created by Micha on 2/3/2025 in #questions

What is the arktype 2 syntax for inferring classes with a private constructor?

In Arktype 1.x I was writing:

import { type, Infer } from 'arktype';

const document = type({
    "ttl?": ["instanceof", TimeStub] as Infer<TimeStub>,
})

import { type, Infer } from 'arktype';

const document = type({
    "ttl?": ["instanceof", TimeStub] as Infer<TimeStub>,
})

But the Infer import is not more available in arktype 2, so I'm wondering how to achieve it now? Maybe the answer could be also added to the docs 🙂 https://arktype.io/docs/objects#instanceof

6 replies

Aarktype

•Created by Micha on 2/3/2025 in #questions

How to create an array of type.instanceOf?

This doesn't work:

const documentReference = type.instanceOf(DocumentReference);

scope({
  user: {
    accounts: "documentReference[]",
  }
}

const documentReference = type.instanceOf(DocumentReference);

scope({
  user: {
    accounts: "documentReference[]",
  }
}

const documentReference = type.instanceOf(DocumentReference);

scope({
  user: {
    accounts: type.instanceOf(DocumentReference)[],
  }
}

const documentReference = type.instanceOf(DocumentReference);

scope({
  user: {
    accounts: type.instanceOf(DocumentReference)[],
  }
}

I only get it working without an array:

const documentReference = type.instanceOf(DocumentReference);

scope({
  account: {
    user: type.instanceOf(DocumentReference),
  }
}

const documentReference = type.instanceOf(DocumentReference);

scope({
  account: {
    user: type.instanceOf(DocumentReference),
  }
}

4 replies

Aarktype

•Created by Micha on 3/17/2024 in #questions

How to specify a property of type function?

In Typescript I have defined it like this:

type User = {
  accounts: accounts?: (() => Promise<Account>)[];
}

type User = {
  accounts: accounts?: (() => Promise<Account>)[];
}

But how to achieve the same in Arktype? PS: Are there any soon plans to extend the Website with more examples? (e.g. the keyword page to explain how they need to be used e.g. Function ) I experience it as quite hard to find answers through the discord search.

11 replies

Aarktype

•Created by Micha on 3/16/2024 in #questions

Why scope().compile().infer resolves to any?

I tried to follow the example here: https://arktype.io/docs/scopes Not sure if this is a bug or if I'm doing it wrong Stackblitz: https://stackblitz.com/edit/rzkceh-eodur9?file=demo.ts%3AL63,index.ts

import { Infer, scope } from "arktype"

export declare class TimeStub {
    readonly isoString: string
    /**
     * @remarks constructor is private to enforce using factory functions
     */
    private constructor()
    /**
     * Creates a new {@link TimeStub} from an ISO date string
     * @param isoString - An ISO date string.
     * @returns A new {@link TimeStub}
     * @throws TypeError if a string is not provided, or RangeError if item
     * is not a valid date
     */
    static from(isoString: string): TimeStub
    /**
     * Creates a new {@link TimeStub} from a Javascript `Date`
     * @param date - A Javascript `Date`
     * @returns A new {@link TimeStub}
     */
    static fromDate(date: Date): TimeStub
    /**
     * Get a copy of the `TimeStub` converted to a Javascript `Date`. Does not
     * mutate the existing `TimeStub` value.
     * @returns A `Date`
     */
    toDate(): Date
    /**
     * Override default string conversion
     * @returns the string representation of a `TimeStub`
     */
    toString(): string
}

export const types = scope({
    timeStub: ["instanceof", TimeStub] as Infer<TimeStub>,
    account: "clientDocument&accountData",
    clientDocument: {
        "id?": "string",
        "coll?": "string",
        "ts?": ["instanceof", TimeStub] as Infer<TimeStub>,
        "ttl?": ["instanceof", TimeStub] as Infer<TimeStub>
    },
    accountData: {
        user: "user|timeStub",
        provider: "provider",
        providerUserId: "string"
    },
    user: {
        name: "string",
        "accounts?": "account[]"
    },
    provider: "'GitHub'|'Google'"
}).compile()

type Account = typeof types.account.infer

import { Infer, scope } from "arktype"

export declare class TimeStub {
    readonly isoString: string
    /**
     * @remarks constructor is private to enforce using factory functions
     */
    private constructor()
    /**
     * Creates a new {@link TimeStub} from an ISO date string
     * @param isoString - An ISO date string.
     * @returns A new {@link TimeStub}
     * @throws TypeError if a string is not provided, or RangeError if item
     * is not a valid date
     */
    static from(isoString: string): TimeStub
    /**
     * Creates a new {@link TimeStub} from a Javascript `Date`
     * @param date - A Javascript `Date`
     * @returns A new {@link TimeStub}
     */
    static fromDate(date: Date): TimeStub
    /**
     * Get a copy of the `TimeStub` converted to a Javascript `Date`. Does not
     * mutate the existing `TimeStub` value.
     * @returns A `Date`
     */
    toDate(): Date
    /**
     * Override default string conversion
     * @returns the string representation of a `TimeStub`
     */
    toString(): string
}

export const types = scope({
    timeStub: ["instanceof", TimeStub] as Infer<TimeStub>,
    account: "clientDocument&accountData",
    clientDocument: {
        "id?": "string",
        "coll?": "string",
        "ts?": ["instanceof", TimeStub] as Infer<TimeStub>,
        "ttl?": ["instanceof", TimeStub] as Infer<TimeStub>
    },
    accountData: {
        user: "user|timeStub",
        provider: "provider",
        providerUserId: "string"
    },
    user: {
        name: "string",
        "accounts?": "account[]"
    },
    provider: "'GitHub'|'Google'"
}).compile()

type Account = typeof types.account.infer

15 replies

Aarktype

•Created by Micha on 3/15/2024 in #questions

How to Union in scope()?

Union 1 will be resolved as I would expect to ts?: string | TimeStub | undefined;:

export const myType = type({
    "id?": "string",
    "coll?": "string",
    "ts?": ["string", "|", ["instanceof", TimeStub] as Infer<TimeStub>]
})

export const myType = type({
    "id?": "string",
    "coll?": "string",
    "ts?": ["string", "|", ["instanceof", TimeStub] as Infer<TimeStub>]
})

But Union 2

export const types = scope({
    account: {
        user: ["user", "|", ["instanceof", TimeStub] as Infer<TimeStub>],
        provider: "provider",
        providerUserId: "string"
    },
    user: {
        name: "string",
        "accounts?": "account[]"
    },
    provider: "'GitHub'|'Google'"
})

export const types = scope({
    account: {
        user: ["user", "|", ["instanceof", TimeStub] as Infer<TimeStub>],
        provider: "provider",
        providerUserId: "string"
    },
    user: {
        name: "string",
        "accounts?": "account[]"
    },
    provider: "'GitHub'|'Google'"
})

will be resolved to

account: { [k in keyof ({
        user: any;
        provider: "GitHub" | "Google";
        providerUserId: string;
    } & {} & {})]: ({
        user: any;
        provider: "GitHub" | "Google";
        providerUserId: string;
    } & {} & {})[k]; };

account: { [k in keyof ({
        user: any;
        provider: "GitHub" | "Google";
        providerUserId: string;
    } & {} & {})]: ({
        user: any;
        provider: "GitHub" | "Google";
        providerUserId: string;
    } & {} & {})[k]; };

although I would expect something like user: User | TimeStub If I'm trying to do the same with the base union syntax that I found "ts?": "string|['instanceof', TimeStub] as Infer<TimeStub>" I get a type error

Type '"string|['instanceof', TimeStub] as Infer<TimeStub>"' is not assignable to type '"string|string" | "string|number" | "string|bigint" | "string|boolean" | "string|symbol" | "string|undefined" | "string|object" | "string|null" | "string|Date" | "string|Error" | ... 25 more ... | "string|parsedDate"'.(2322)
demo.ts(44, 5): The expected type comes from property 'ts?' which is declared here on type '{ "id?": "string"; "coll?": "string"; "ts?": "string|string" | "string|number" | "string|bigint" | "string|boolean" | "string|symbol" | "string|undefined" | "string|object" | "string|null" | ... 27 more ... | "string|parsedDate"; }'

Type '"string|['instanceof', TimeStub] as Infer<TimeStub>"' is not assignable to type '"string|string" | "string|number" | "string|bigint" | "string|boolean" | "string|symbol" | "string|undefined" | "string|object" | "string|null" | "string|Date" | "string|Error" | ... 25 more ... | "string|parsedDate"'.(2322)
demo.ts(44, 5): The expected type comes from property 'ts?' which is declared here on type '{ "id?": "string"; "coll?": "string"; "ts?": "string|string" | "string|number" | "string|bigint" | "string|boolean" | "string|symbol" | "string|undefined" | "string|object" | "string|null" | ... 27 more ... | "string|parsedDate"; }'

https://stackblitz.com/edit/rzkceh-eodur9?file=demo.ts

6 replies

Aarktype

•Created by Micha on 3/15/2024 in #questions

How to include an external class into an arktype type?

I tried

import { TimeStub } from 'fauna'; // class

const clientDocument = type({
    'id?': 'string',
    'coll?': 'string',
    'ts?': TimeStub
});

import { TimeStub } from 'fauna'; // class

const clientDocument = type({
    'id?': 'string',
    'coll?': 'string',
    'ts?': TimeStub
});

and

import { TimeStub } from 'fauna'; // class

const clientDocument = type({
    'id?': 'string',
    'coll?': 'string',
    'ts?': ['instanceof', TimeStub]
});

import { TimeStub } from 'fauna'; // class

const clientDocument = type({
    'id?': 'string',
    'coll?': 'string',
    'ts?': ['instanceof', TimeStub]
});

but both create a Type<never> for me. I'm using arktype 1.0.29-alpha

21 replies

Aarktype

•Created by Micha on 3/1/2024 in #questions

Are you recommending to create first ArkType types and derive from their TS types or vice versa?

2 replies

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