What does "Return" do in scripting?

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#1

Hey! I’m wondering what return does in roblox lua scripting. Any help would be greatly appreciated! Thanks! :happy1:

#2

In a ordinary normal script function, it does what the keyword does.

for example

local a = 2
local b = 4

local function Sum(num0, num1)
    return num0 + num1 -- Returns the sum of the 2 numbers
end

print(Sum(a, b)) -- 6
#3

Is there any good use cases for return?

#4
#5

There exists a version of return where its on a module script, if you know about it, it is like a package that you can call require() on it and access the functions you have built inside it

#6

If you want to exit a function if a condition exists you can place a return in an if then statement: i.e. “if not variableX then return end” I use that often, helps avoid errors in functions like if an object no longer exists after a delay

#7

In all (most) languages, there is a return keyword. This is used in various different ways, but will return the specified value from the function scope. IE:

Say we want a function that ‘returns’ the distance between two humanoids:

local function getDistance(humanoid1, humanoid2)
	local humanoid1rootpart = humanoid1.Parent.PrimaryPart
	local humanoid2rootpart = humanoid2.Parent.PrimaryPart
	
	return (humanoid1rootpart.Position - humanoid2rootpart.Position).magnitude
end

Now, we can call this function with the provided arguments and it will give us the distance between the two humanoids.

local h1 = someHumanoid
local h2 = someHumanoid2
local distance = getDistance(h1, h2)

if distance > 10 then
	print("Distance is too large")
else
	print("Distance is close enough")
end

Here are few more small module methods showcasing the use of returns for my game I am working on:

--Gets a random point near a point, within radius
function module.getRandomPointNearPoint(v3d, radius)
	radius = radius * 10
	local rp = Vector3.new(
		module.random(radius *-1, radius),
		0,
		module.random(radius*-1,radius))
	rp = rp + v3d
	return rp
end

--Gets a random vector between two vectors
function module.randomVectorBetween(v3d1, v3d2)
	local x = module.random(v3d1.X,v3d2.X)
	local y = module.random(v3d1.Y, v3d2.Y)
	local z = module.random(v3d1.Z, v3d2.Z)
	return Vector3.new(x,y,z)
end

--Gets the Players->Player by name.
--If you need the serverside client, 
--use .getWorkspaceClient method
function module.playerByName(name)
	local playerGroup = game.Players:GetPlayers();
	for i,pl in pairs(playerGroup) do
		if(string.lower(pl.Name) == string.lower(name)) then
			return pl
		end
	end
	return false
end
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#8

return can be used to return a value back to a function to make that function become the value that you return to the function it also can be used to break a function

function add(a, b)
    return a + b
end

local sum = add(5, 3)  -- sum will be 8
print(sum)  -- Output: 8

function processNumber(num)
    if num < 0 then
        print("Negative numbers are not allowed.")
        return  -- Exits the function immediately
    end
end
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