Union to Intersection

introduction

Implement the advanced util type UnionToIntersection<U>

For example

ts
type I = Union2Intersection<'foo' | 42 | true>; // expected to be 'foo' & 42 & true

ts
type I = Union2Intersection<'foo' | 42 | true>; // expected to be 'foo' & 42 & true

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start point

ts
/* _____________ Your Code Here _____________ */
type UnionToIntersection<U> = any
 
/* _____________ Test Cases _____________ */
type cases = [
    Expect<Equal<UnionToIntersection<'foo' | 42 | true>, 'foo' & 42 & true>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
    Expect<Equal<UnionToIntersection<(() => 'foo') | ((i: 42) => true)>, (() => 'foo') & ((i: 42) => true)>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
]Try

ts
/* _____________ Your Code Here _____________ */
type UnionToIntersection<U> = any
 
/* _____________ Test Cases _____________ */
type cases = [
    Expect<Equal<UnionToIntersection<'foo' | 42 | true>, 'foo' & 42 & true>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
    Expect<Equal<UnionToIntersection<(() => 'foo') | ((i: 42) => true)>, (() => 'foo') & ((i: 42) => true)>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
]Try

take the challenge

my solutions

Spoiler warning // Click to reveal answer

ts
type UnionToIntersection<U> = (U extends any ? (arg: U) => any : never) extends (
  arg: infer I
) => void
  ? I
  : never;Try

ts
type UnionToIntersection<U> = (U extends any ? (arg: U) => any : never) extends (
  arg: infer I
) => void
  ? I
  : never;Try

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