just function on typescript which type code example

Example 1: types function typescript

interface Safer_Easy_Fix {
    title: string;
    callback: () => void;
}
interface Alternate_Syntax_4_Safer_Easy_Fix {
    title: string;
    callback(): void;
}

Example 2: typescript function type

interface Date {
  toString(): string;
  setTime(time: number): number;
  // ...
}