vue/types/common.d.ts

Reactive, component-oriented view layer for modern web interfaces.

export type Data = { [key: string]: unknown }

export type UnionToIntersection<U> = (
  U extends any ? (k: U) => void : never
) extends (k: infer I) => void
  ? I
  : never

// Conditional returns can enforce identical types.
// See here: https://github.com/Microsoft/TypeScript/issues/27024#issuecomment-421529650
// prettier-ignore
type Equal<Left, Right> =
  (<U>() => U extends Left ? 1 : 0) extends (<U>() => U extends Right ? 1 : 0) ? true : false;

export type HasDefined<T> = Equal<T, unknown> extends true ? false : true