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Shift

介绍​

Implement the type version of Array.shift

ts
type Result = Shift<[3, 2, 1]> // [2, 1]
ts
type Result = Shift<[3, 2, 1]> // [2, 1]
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起点​

ts
/* _____________ Your Code Here _____________ */
 
  type Shift<T> = any
 
/* _____________ Test Cases _____________ */
 
type cases = [
  // @ts-expect-error
Unused '@ts-expect-error' directive.2578Unused '@ts-expect-error' directive.
  Shift<unknown>,
  Expect<Equal<Shift<[]>, []>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
  Expect<Equal<Shift<[1]>, []>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
  Expect<Equal<Shift<[3, 2, 1]>, [2, 1]>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
  Expect<Equal<Shift<['a', 'b', 'c', 'd']>, ['b', 'c', 'd']>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
]
ts
/* _____________ Your Code Here _____________ */
 
  type Shift<T> = any
 
/* _____________ Test Cases _____________ */
 
type cases = [
  // @ts-expect-error
Unused '@ts-expect-error' directive.2578Unused '@ts-expect-error' directive.
  Shift<unknown>,
  Expect<Equal<Shift<[]>, []>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
  Expect<Equal<Shift<[1]>, []>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
  Expect<Equal<Shift<[3, 2, 1]>, [2, 1]>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
  Expect<Equal<Shift<['a', 'b', 'c', 'd']>, ['b', 'c', 'd']>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.
]
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解决方案​

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ts
type Shift<T extends any[]> = T extends [infer F, ...infer R] ? R : [];
 
 
 
ts
type Shift<T extends any[]> = T extends [infer F, ...infer R] ? R : [];
 
 
 
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