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获取元祖长度
创建一个通用的Length,接受一个readonly的数组,返回这个数组的长度。
例如:
ts
type tesla = ['tesla', 'model 3', 'model X', 'model Y']
type spaceX = ['FALCON 9', 'FALCON HEAVY', 'DRAGON', 'STARSHIP', 'HUMAN SPACEFLIGHT']
type teslaLength = Length<tesla> // expected 4
type spaceXLength = Length<spaceX> // expected 5
- 请在下面作答:
查看解答
ts
type Length<T extends readonly any[]> = T['length']