Question

我有一个数据结构，它基本上是嵌套列表/字典的混合：

class System:
    def __init__(self, name, subsystems, uri):
        self.name = name
        self.subsystems = subsystems
        self.uri = uri

A = System("A", [], "http://A")
B1 = System("B1", [], "http://B/B1")
B21 = System("B12", [], "http://B/B2/B21")
B22 = System("B22", [], "http://B/B2/B22")
B2 = System("B2", [B21, B22], "http://B/B2")
B = System("B", [B1, B2], "http://B")
C1 = System("C1", [], "http://C/C1")
C = System("C", [C1], "http://C")
S = System("S", [A, B, C], None)

在Python中，我编写了以下递归生成器：

def find_subsystem(system, name):
    if system.name == name:
        yield system.uri
    for sub in system.subsystems:
        yield from find_subsystem(sub, name)

允许我像

那样进行“查询”

next(find_subsystem(S, "B22"))
#=> 'http://B/B2/B21'

或

list(find_subsystem(S, "B22"))
#=> ['http://B/B2/B21', 'http://B/B2/B22']

我想知道如何才能最好地在JavaScript中编写一个等价物：我知道我可以用yield做一些事情，但我认为由于yield from，Python代码非常干净。是用JavaScript还是常用成语？

（我可以猜测使用来自underscore.js的东西，但我想“手动”做这个练习）

Answer 1

关注@vaultah评论后，我使用yield*获得了以下解决方案：

function System(name, subsystems, uri) {
    this.name = name;
    this.subsystems = subsystems;
    this.uri = uri;
}
var A = new System("A", [], "http://A");
var B1 = new System("B1", [], "http://B/B1");
var B21 = new System("B21", [], "http://B/B2/B21");
var B22 = new System("B22", [], "http://B/B2/B22");
var B2 = new System("B2", [B21, B22], "http://B/B2");
var B = new System("B", [B1, B2], "http://B");
var C1 = new System("C1", [], "http://C/C1");
var C = new System("C", [C1], "http://C/");
var S = new System("S", [A, B, C], "");

function* find_subsystem(system, name) {
    if(system.name == name) {
        yield system.uri;
    }
    for (var i = 0; i < system.subsystems.length; i++) {
        yield* find_subsystem(system.subsystems[i], name);
    }
}

console.log(find_subsystem(S, "B22").next().value);

Javascript相当于Python的'yield from'

1 个答案: