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[SOLVED] How to run a function once in Object-Oriented Programming?

Asked by

T3_MasterGamer 2189

2 years ago

Edited 2 years ago

Hello. I'm trying to make my own Custom Signal module without using BindableEvents nor using a module from the DevForum. But I don't know how to make the handler Signal:Once() which basically uses Connect but only does it once. I tried using coroutines, debounce, and setting the function to nil, but it still runs more than once like Signal:Connect() and not like RBXScriptSignal:Once(). Here's the module for reference:

01local module = {}
02module.__index = module
03 
04local backupBindableEvent = Instance.new("BindableEvent")
05 
06function module.new(signalName: string)
07    local self = setmetatable({}, module)
08    local newSignal = {}
09 
10    local newSignalName: string
11 
12    if signalName ~= nil then
13        newSignalName = signalName
14    else
15        newSignalName = "Event"
16    end
17 
18    self._listeners = require(script.Listeners).new()
19    local listenersModule = self._listeners
20 
21    function newSignal:Connect(func)
22        listenersModule:AddListener(func)
23 
24        return {
25            Connected = true,
26            Disconnect = function(self)
27                listenersModule:RemoveListener(func)
28                self.Connected = false
29            end
30        }
31    end
32 
33    function newSignal:ConnectParallel(func)
34        task.desynchronize()
35        listenersModule:AddListener(func)
36        return {
37            Connected = true,
38            Disconnect = function(self)
39                listenersModule:RemoveListener(func)
40                self.Connected = false
41            end
42        }
43    end
44 
45    function newSignal:Once(func)
46        return backupBindableEvent.Event:Once(func) -- using BindableEvents until i figured it out!
47    end
48 
49    function newSignal:Wait()
50        return backupBindableEvent.Event:Wait() -- using BindableEvents until i figured it out!
51    end
52 
53    self[newSignalName] = newSignal
54 
55    return self
56end
57 
58function module:Fire(...: any)
59    local paramsTable = table.pack(...)
60 
61    backupBindableEvent:Fire(table.unpack(paramsTable))
62 
63    task.defer(function()
64        local listenersModule = self._listeners
65 
66        repeat task.wait() until listenersModule:GetListenersAsync() ~= nil
67        local listenersTable = listenersModule:GetListenersAsync()
68 
69        if listenersTable ~= nil then
70            for _, listenerFunc in pairs(listenersTable) do
71                task.defer(function()
72                    listenerFunc(table.unpack(paramsTable))
73                end)
74            end
75        end
76    end)
77end
78 
79return module
 View all 79 lines...

Also I don't know how to make the Signal:Wait() function. Right now, I'm temporarily using BindableEvents to make those functions work.

And also, if you noticed anything wrong in my module that is off-topic, lemme know!

Wait will be almost the same as :Once but at the end instead of returning, do a repeat wait() until not myTable.Connected blowup999 659 — 2y

1 answer

Answered by

blowup999 659

2 years ago

It's hard to help here because this is highly dependent on the listenersModule you have - Personally, I would add an :AddOnce(func) in addition to :AddListener(func) and let that module handle it, but this also runs into the issue of the Connected variable being different from reality.

Easiest way with given code is:

01function newSignal:Once(func)
02    local myTable = {Connected = true}
03    local function singleUse()
04        myTable:Disconnect()
05        func()
06    end
07    listenersModule:AddListener(singleUse)
08    function myTable:Disconnect()
09        listenersModule:RemoveListener(singleUse)
10        myTable.Connected = false
11    end
12    return myTable
13end

The listenersModule has 3 functions: :AddListener(), :RemoveListener(), and :GetListenersAsync(). The listenersModule just simply creates an array of functions T3_MasterGamer 2189 — 2y

I also need help in making the :Wait() function. Thanks! T3_MasterGamer 2189 — 2y

But sure, I’ll try to make an :AddOnce() function. T3_MasterGamer 2189 — 2y

Sadly, yours did not work but I finally solved the :Once() function. I just converted the listener to a thread, and closed it once it was fired to avoid of doing it again. T3_MasterGamer 2189 — 2y

[SOLVED] How to run a function once in Object-Oriented Programming?

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