4
谁能解释一下为什么这条 TypeScript 离谱地没有报错？
source link: https://www.v2ex.com/t/864816
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declare type KeyGetter = (obj: unknown) => string
// 取自 lodash
declare const identity: {
<T>(value: T): T
(): undefined
}
declare const identity2: {
<T>(value: T): T
}
declare const identity3: {
(): undefined
}
let a: KeyGetter = identity // 为啥没报错?!类型不安全了吧
let b : KeyGetter = identity2 // 正常报错
let c: KeyGetter = identity3 // 正常报错
第一个 identity 类型是什么意思？不是一个重载吗？
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