Typescript type

example.ts

interface I1 {
  p1: (a: boolean)=>void
  p2: (a: string) => void
  p3: (a: number) => void
}

const v1:I1 = 0 as any

function f1<T extends keyof I1>(
  name: T,
  arg: Parameters<I1[T]>[0]
){
  v1[name](arg)
}