Is there a way to break a while loop outside it?

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8 years ago

I want to make a while loop that breaks when a function is called,but i don't know how to do it! Here is the while loop of my script and the function that breaks the loop

01while true do
02    script.Parent.TweenableValue.Tween:Invoke(thing,'InOut','Quad',20,true)
03    repeat
04        wait()
05    until value.Value==thing
06    script.Parent.TweenableValue.Tween:Invoke(-thing,'InOut','Quad',20,true)
07    repeat
08        wait()
09    until value.Value==-thing
10    print'done'
11end
12 
13function play()
14    print'play'
15    killplayer:FireServer()
16    menuSound:Stop()
17    button.Visible=false
18    con:disconnect()
19    script.Parent.ImageLabel.Visible=false
20    script.Parent.Frame.BackgroundTransparency=0
21    --Break while loop
22end
 View all 22 lines...

Have a variable set to true, and instead of while true do, use while VarName do. Then set the bool to false in the function? iamnoamesa 674 — 8y

^ Yeah, that works AstrealDev 728 — 8y

Answer

To answer your question, though, you would want the condition of your while loop to be mutable (not constant). That way, you can change the variable the while loop is using as a condition, to terminate the loop next iteration. Example:

01local running = true -- Create condition
02 
03-- This is what I was talking about before, with the involvement of coroutines. While this is a solution, I highly don't recommend it for anything other than practice.
04spawn(function()
05    while running do
06        print("Loop is running")
07        wait()
08    end
09    print("Stopped running")
10end)
11 
12-- Some function that stops the loop outside of itself by setting 'running' to false
13local function stopRunning()
14    running = false
15end
16 
17-- Wait 1 second before stopping the loop
18wait(1)
19stopRunning()

The code above is just for practice, I don't recommend using it in any project you're working on. However, this would be the answer to your question. If need help understanding anything, just let me know.

Edit:

Adding a "pause and play" mechanic

Creating a "pause and play" mechanic to a loop, would implement coroutines. You don't have to use them directly, but they're being used one way or another (with other functions like spawn), so I'm going include them in my example.

01-- ~ ScriptGuider
02-- Library functions
03local create = coroutine.create
04local resume = coroutine.resume
05local yield = coroutine.yield
06local status = coroutine.status
07local floor = math.floor
08 
09-- A pseudo instance to provide interface for a loop
10local loop = {}
11 
12-- Local pause function, to be used within the loop's code.
13local function Pause()
14    print("Loop paused from internal coroutine")
15    loop.Running = false
16    return yield()
17end
18 
19-- Code that will be run within the while loop.
20loop.Code = function(t)
21    print("Loop birth time: "..t.." seconds")
22    Pause() -- Calling "Pause" to stop the loop until ran externally
23    print("Picking up") -- Picks up where it left off when ran again
24    wait(1) -- Wait 1 second each iteration
25end
26 
27function loop:Run()
28    local coro = self.Coro
29    -- Using a debounce here so we can't resume and already running coroutine
30    if not self.Running then
31        self.Running = true
32        -- Make sure we always have a coroutine to resume
33        if not coro or coro and status(coro) ~= "suspended" then
34            coro = create(function()
35                local timestamp = tick()
36                -- The actual running loop
37                while self.Running do
38                    local elapsed = floor(tick() - timestamp)
39                    -- You could just "return true" from within the loop's "Code" function to stop the loop
40                    if loop.Code(elapsed) == true then
41                        print("Loop stopped from internal coroutine")
42                        break
43                    end
44                end
45            end)
46            self.Coro = coro
47        end
48        resume(coro)
49    end
50end
51 
52-- Stop the loop from outside it's coroutine
53function loop:Stop()
54    print("Loop stopped from external coroutine")
55    self.Running = false
56end
57 
58-- Run the loop
59loop:Run()
60wait(5)
61-- Stop the loop
62loop:Stop()
63wait(5)
64-- Run the loop again
65loop:Run()
 View all 65 lines...

Looks a bit complicated, as it should for a situation like this. This is probably the closest I could get to giving an example without making an entire task-scheduler. This basically just utilizes the yield function of the coroutine library, which exits the code block's running state, and can be used to queue it up to later be resumed. During this intermediate state, the program can spend time handling other tasks so no time is wasted.

Is there a way to break a while loop outside it?

1 answer

Synopsis

Answer

Adding a "pause and play" mechanic

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