Is there something wrong in this Boolean script?

Is there something wrong with this script? Studio crashes every time I run a test with this script I made:

e1 = script.Parent.EmergencyLight1
e2 = script.Parent.EmergencyLight2
e3 = script.Parent.EmergencyLight3
e4 = script.Parent.EmergencyLight4
e5 = script.Parent.EmergencyLight5
es = script.Parent.EmergencyLightSc
val = script.Parent.Value.Value

while true do
	if val == true then 
		e1.SpotLight.Enabled = true
		e1.SpotLight2.Enabled = true
		e2.SpotLight.Enabled = true
		e2.SpotLight2.Enabled = true
		e3.SpotLight.Enabled = true
		e3.SpotLight2.Enabled = true
		e4.SpotLight.Enabled = true
		e4.SpotLight2.Enabled = true
		e5.SpotLight.Enabled = true
		e5.SpotLight2.Enabled = true
		es.SpotLight.Enabled = true
		es.SpotLight2.Enabled = true
		es.SurfaceGui.TextLabel.Visible = true
	else
		e1.SpotLight.Enabled = false
		e1.SpotLight2.Enabled = false
		e2.SpotLight.Enabled = false
		e2.SpotLight2.Enabled = false
		e3.SpotLight.Enabled = false
		e3.SpotLight2.Enabled = false
		e4.SpotLight.Enabled = false
		e4.SpotLight2.Enabled = false
		e5.SpotLight.Enabled = false
		e5.SpotLight2.Enabled = false
		es.SpotLight.Enabled = false
		es.SpotLight2.Enabled = false
		es.SurfaceGui.TextLabel.Visible = false
		end
end

#Why does Studio crash? The reason that Studio crashes is because you have, by what you have written, instructed the computer to endlessly devote all of its resources to checking the truth of a boolean value and then setting the properties of various lights.

while true do
--Your code here
end

That is the purpose of a while loop, to continue checking the condition and then executing the contents until either the computer fails, the boolean condition is broken, or until the loop yields.

You want the loop to yield - that means to surrender its current processes for a time interval, allowing the computer to handle different tasks instead of this one loop.

The most straightforward way to yield any process is to make a call to the wait() function. You should have the loop wait() a little bit each time through the loop, for example:

while true do
	wait()
	if val == true then
		--Do stuff with your lights
	end
end

You should see the description of wait() on the Official ROBLOX Wiki and also read this blog article about using wait()

According to the Lua 5.1 Reference Manual, anything that is not false or nil will evaluate to true in a boolean expression, and because of that, many people use this 'shorthand' notation when writing while loops:

while wait() do
	if val == true then
		--do stuff with your lights
	end
end

#Value Instances We'd need to know more about what script.Parent.Value.Value is to properly answer this, but I'm guessing that it's referring to the Value property of an Instance that is a child of script.Parent and is called "Value". If this is the case, I recommend naming it something more descriptive, for clarity, such as "LightSwitch" or "EmergencyToggle". That line would then become:

val = script.Parent.LightSwitch.Value

There is another slight problem here, though. The line above stores the current boolean value of the LightSwitch BoolValue Instance in a variable, it does not keep a reference to the Instance itself. What this means is that when LightSwitch.Value changes, val will not change. To avoid this problem, you'll want to store a reference to the BoolValue Instance itself:

switch = script.Parent.LightSwitch

Then in your loop, check the Value property of switch like-so:

if switch.Value == true then
	--Do things
end

#Tip switch.Value is a boolean value; it has a value of either true or false. Therefore, for ease of writing, you don't need to use the expression if switch.Value == true, instead you can just write if switch.Value.

Putting it all together, you now have this loop to work with:

switch = script.Parent.LightSwitch

while wait() do
	if switch.Value then
		--Lights on
	else
		--Lights off
	end
end

Make sure to read the blog article about using wait() Edit: The ultimate condition should be switch.Value, not just switch