Question

我有一个导入当前组件的汽车模型。试图将一组汽车声明为其中一个函数的返回类型。但编译器无法识别汽车阵列类型。你能帮忙吗？

carcomponent.ts

     import  { Car } from '../models/car';

     export class carComponent implements onInit {
        public car : Car;

        carsavailable(): Car[] { //delcaring Car[] is not recognized.

        }

     }

car.ts .......

     export class Car {
          name: string;
     }

错误

编译器用红色强调Car []，并说＆＃39;一个函数，其delcared类型既不是＆＃39; void＆＃39;也没有任何＆＃39;必须返回一个值。

我是否必须在某处插入汽车或更改返回类型声明方式。

Answer 1

因为您没有从函数返回任何值，所以编译器显示错误

from concurrent.futures import ProcessPoolExecutor
import time
import random


def worker1(arg):
    time.sleep(random.random())
    return arg


def pipe12(future):
    pool2.submit(worker2, future.result()).add_done_callback(pipe23)


def worker2(arg):
    time.sleep(random.random())
    return arg


def pipe23(future):
    pool3.submit(worker3, future.result()).add_done_callback(spout)


def worker3(arg):
    time.sleep(random.random())
    return arg


def spout(future):
    print(future.result())


if __name__ == "__main__":
    __spec__ = None  # Fix multiprocessing in Spyder's IPython
    pool1 = ProcessPoolExecutor(2)
    pool2 = ProcessPoolExecutor(2)
    pool3 = ProcessPoolExecutor(2)
    for i in range(10):
        pool1.submit(worker1, i).add_done_callback(pipe12)
    pool1.shutdown()
    pool2.shutdown()
    pool3.shutdown()

Answer 2

您正在声明一个返回类型的方法，因此它应该返回一个值

carsavailable(): Car[] { 
     return [];
}

将自定义对象的数组类型声明为typescript函数

2 个答案: