michlbro/Javelin

An unique event library for Roblox.

Javelin

An unique event library for Roblox.

What is Javelin?

Javelin is a open source single-module roblox library for custom event handling. It takes an approach similar to NodeJS events, giving a advantage over other forms of custom events.

Instead of a class representing a event, it has a class that can listen and emit to variable number of events.

local lance = Javelin.new()

lance:On("throw", function()
    print("The lance was thrown!")
end)

lance:On("break", function(whoBrokeIt)
    print(whoBrokeIt.." broke the lance!")
end)

lance:Emit("throw")
lance:DelayEmit(1, "break", "I")

This solves a common issue of other custom event implementations, which mimics RBXScriptSignal and require you to type every single event by hand.

local node = {
  created = Event.new(),
  destroyed = Event.new(),
  changed = Event.new(),
  childadded = Event.new(),
  -- more unnecessary event defining
}

As a Custom Event handler, it's planned to be used in classes, Javelin.extend allows you to take a new instance of a class and extend it with Javelin, instead of creating a value for it.

-- bad alternative
function myClass.new()
    local self = setmetatable({}, myClass)
    self.signal = Javelin.new()
    return self
end

-- intended purpose
function myClass.new()
    local self = Javelin.extend(myClass, {
        -- insert properties here
    })
    return self
end

Javelin also will warn you if you write redundant or weird code with it, you may disable/enable them by using Javelin.diagnostic(diagnosticId, mode)

local myJavelin = Javelin.new()
myJavelin:Emit("emitted") -- [Code '1']: Attempt to emit event '%s' that has no listeners.
Javelin.diagnostic(1, false)
myJavelin:Emit("emitted") -- no output

Where to use Javelin?

Javelin is general purpose, meaning it can be used in anything, but there's a few use cases that were designed for it.

• Very useful on creating classes that has many events, since Javelin creates the events when you start listening to them, making you not to worry about creating the events.
• Can also work just as a standalone event handler for handling game events, such as intermission.

How I can contribute to Javelin?

If you find a bug or you want to add a feature, create an Issue/Pull Request for it, I will respond to it fast as possible.

I'm on the process of creating documentation, any suggestions/contribuitions please deliver me a DM on Discord: letiul.