javascript - 简单构造函数中的流类型错误

Question

为什么 flowtype 报告以下错误以及需要如何记录该错误才能按预期工作？

index.js:7
  4: console.log(MY_OBJECT.getName());
                           ^^^^^^^ property `getName`. Property not found in
  4: console.log(MY_OBJECT.getName());
                 ^^^^^^^^^ new object

index.js

// @flow
import {MyObject} from './object';
const MY_OBJECT = new MyObject('name');
console.log(MY_OBJECT.getName());

对象.js:

// @flow
export function MyObject(name: string) {
    this._name = name;
    this.getName = function (): string {return this._name;};
    this.setName = function (name: string) {this._name = name;};
}

Answer 1

Flow 不喜欢这种风格。当您在同一个模块中使用它时，它会工作，但是当您从另一个文件导入它时，它不会。

建议使用ES2015 class syntax相反:

// @flow
export class MyObject {
    name: string;

    constructor(name: string){
        this.name = name;
    }

    getName() {
        return this.name;
    }

    setName(name: string) {
        this.name = name;
    }
}

如果你不喜欢这个，你可以使用原型(prototype)，即 has limited support :

// @flow
export function MyObject(name: string) {
  this._name = name;        
}

MyObject.prototype.getName = function (): string {return this._name;};
MyObject.prototype.setName = function (name: string) {this._name = name;};