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IsEqual<A, B>

IsEqual<A, B> = <G>() => G extends A & G | G ? 1 : 2 extends <G>() => G extends B & G | G ? 1 : 2 ? true : false

Defined in: packages/react-querybuilder/src/types/type-fest/is-equal.ts:26

Returns a boolean for whether the two given types are equal.

Type Parameters​

Type Parameter
A
B

https://github.com/microsoft/TypeScript/issues/27024#issuecomment-421529650

https://stackoverflow.com/questions/68961864/how-does-the-equals-work-in-typescript/68963796#68963796

Use-cases:

  • If you want to make a conditional branch based on the result of a comparison of two types.

Example​

import type {IsEqual} from 'type-fest';

// This type returns a boolean for whether the given array includes the given item.
// `IsEqual` is used to compare the given array at position 0 and the given item and then return true if they are equal.
type Includes<Value extends readonly any[], Item> =
	Value extends readonly [Value[0], ...infer rest]
		? IsEqual<Value[0], Item> extends true
			? true
			: Includes<rest, Item>
		: false;
caution

API documentation is generated from the latest commit on the main branch. It may be somewhat inconsistent with official releases of React Query Builder.