2.0.0-beta.0

Generics

Native generic syntax is finally available! 🎉

Here are some examples of how this powerful feature can be used:

Standalone Type Syntax

const boxOf = type("<t>", { box: "t" })

const schrodingersBox = boxOf({ cat: { isAlive: "boolean" } })

const expected = type({
	box: {
		cat: { isAlive: "boolean" }
	}
})

// true
console.log(expected.equals(schrodingersBox))

Constrained Parameters

All syntax in parameters definitions and all references to generic args are fully-type safe and autocompleted like any builtin keyword. Constraints can be used just like TS to limit what can be passed to a generic and allow that arg to be used with operators like >.

const nonEmpty = type("<arr extends unknown[]>", "arr > 0")
const nonEmptyNumberArray = nonEmpty("number[]")

const expected = type("number[] > 0")

// true
console.log(expected.equals(nonEmptyNumberArray))

Scoped

There is a special syntax for specifying generics in a scope:

const types = scope({
	"box<t, u>": {
		box: "t | u"
	},
	bitBox: "box<0, 1>"
}).export()

const expected = type({ box: "0|1" })

// true
console.log(expected.equals(types.bitBox))

Builtins

Record is now available as a builtin keyword.

const stringRecord = type("Record<string, string>")

const expected = type({
	"[string]": "string"
})

// true
console.log(expected.equals(stringRecord))

Other common utils like Pick and Omit to follow in the an upcoming release.

Recursive and cyclic generics are also currently unavailable and will be added soon.

For more usage examples, check out the unit tests for generics here.

This feature was built to be very robust and flexible. We're excited to see what you do with it!

Fix narrowing output of some piped unions

In recent versions, types like the following would fail to parse:

// Previously was a ParseError, now correctly inferred as
// (In: string | number) => Out<of<bigint, Narrowed>>
const Amount = type("string|number")
	.pipe(v => BigInt(v))
	.narrow(b => b > 0n)

@arktype/[email protected]

ci: fix publish script

@arktype/[email protected]

ci: fix publish script

@arktype/[email protected]

ci: fix publish script

@arktype/[email protected]

ci: fix publish script

@ark/[email protected]

ci: fix publish script

@ark/[email protected]

ci: fix publish script

@ark/[email protected]

ci: fix publish script

@ark/[email protected]

ci: fix publish script

@ark/[email protected]

ci: fix publish script