原型

//Prototype
class Shape {
    public lineCount = 0

    constructor(lineCount: number) {
        this.lineCount = lineCount
    }

    clone() {
        return new Shape(this.lineCount)
    }
}

//ConcretePrototype
class Square extends Shape {
    constructor() {
        super(4)
    }

    clone() {
        return new Square()
    }
}

//Client
class ShapeMaker {
    private _shape: Shape

    constructor(shape: Shape) {
        this._shape = shape;
    }

    makeShape() {
        return this._shape.clone()
    }
}

let square = new Square()
let maker = new ShapeMaker(square)

let square1 = maker.makeShape()
let square2 = maker.makeShape()

console.log("square1.lineCount is",
    square1.lineCount)
console.log("square2.lineCount is",
    square2.lineCount)