Locking by string. Is this safe/sane?

Question

I need to lock a section of code by string. Of course the following code is hideously unsafe:

lock(\"http://someurl\")
{
    //bla
}

So I\'

Answer 1

In most cases, when you think you need locks, you don't. Instead, try to use thread-safe data structure (e.g. Queue) which handles the locking for you.

For example, in python:

class RequestManager(Thread):
    def __init__(self):
        super().__init__()
        self.requests = Queue()
        self.cache = dict()
    def run(self):        
        while True:
            url, q = self.requests.get()
            if url not in self.cache:
                self.cache[url] = urlopen(url).read()[:100]
            q.put(self.cache[url])

    # get() runs on MyThread's thread, not RequestManager's
    def get(self, url):
        q = Queue(1)
        self.requests.put((url, q))
        return q.get()

class MyThread(Thread):
    def __init__(self):
        super().__init__()
    def run(self):
        while True:
            sleep(random())
            url = ['http://www.google.com/', 'http://www.yahoo.com', 'http://www.microsoft.com'][randrange(0, 3)]
            img = rm.get(url)
            print(img)