ts中的泛型

1. 泛型函数示例：

 
function reverse<T>(arr: T[]): T[] {
  return arr.reverse();
}
const numbers = [1, 2, 3, 4, 5];
const reversedNumbers = reverse<number>(numbers); // [5, 4, 3, 2, 1]
const strings = ["apple", "banana", "orange"];
const reversedStrings = reverse<string>(strings); // ["orange", "banana", "apple"]

2. 泛型接口示例：

 
interface Pair<T, U> {
  first: T;
  second: U;
}
const pair: Pair<number, string> = { first: 1, second: "apple" };
console.log(pair.first); // 1
console.log(pair.second); // "apple"

3. 泛型类示例：1111111111111111111111111

 
class Queue {
  private elements: T[] = [];
  enqueue(element: T): void {
    this.elements.push(element);
  }
  dequeue(): T | undefined {
    return this.elements.shift();
  }
}
const queue = new Queue();
queue.enqueue(1);
queue.enqueue(2);
console.log(queue.dequeue()); // 1
console.log(queue.dequeue()); // 2

4. 泛型约束示例：

 
interface Shape {
  readonly x: number;
  readonly y: number;
}
function printShape<T extends Shape>(shape: T): void {
  console.log(`Shape at (${shape.x}, ${shape.y})`);
}
const rectangle = { x: 10, y: 20, width: 30, height: 40 };
printShape(rectangle); // Shape at (10, 20)

5. 泛型函数类型示例：

 
type MathOperation<T> = (a: T, b: T) => T;
const add: MathOperation<number> = (a, b) => a + b;
console.log(add(3, 4)); // 7
const concat: MathOperation<string> = (a, b) => a + b;
console.log(concat("hello", "world")); // "helloworld"