LÖVE

checkbox.study.checkboxSystem = system(
{"name", "=selected", "x", "y", "w", "h", "-study"},
function(name, selected, bx, by, w, h, mx, my, button)
	if selected == 0 and button == 1 and mx > bx and mx < bx+w and my > by and my < by+h then
		selected = 1
	elseif selected == 1 and button == 1 and mx > bx and mx < bx+w and my > by and my < by+h then
		selected = 0
	end
	return selected
end)

checkbox.study.checkboxSystem = system(
{"name", "=selected", "x", "y", "w", "h", "-study"},
function(name, selected, bx, by, w, h, mx, my, button)
	if selected == 0 and button == 1 and mx > bx and mx < bx+w and my > by and my < by+h then
		return 1
	end
	if selected == 1 and button == 1 and mx > bx and mx < bx+w and my > by and my < by+h then
		return 0
	end
	return selected
end)

checkbox.study.checkboxSystem = system(
{"name", "=selected", "x", "y", "w", "h", "-study"},
function(name, selected, bx, by, w, h, mx, my, button)
	if button == 1 and mx > bx and mx < bx+w and my > by and my < by+h then
		return -selected + 1 -- toggle between 1 and 0
		-- or use true/false instead and `return not selected`
	end
	return selected
end)

So, I cannot describe how parameters works with a general statement or logic such as it just makes a copy of the variable, or it just pass what's inside a variable, or the variable itself. To explain it properly it's necessary to point out all the rules and exceptions.

I understand your confusion. Here's one way to think about it: passing a value into a function always makes a copy of that value. But, when we're talking about things like tables and functions, "value" means something like a reference to the "actual" table or function, and the "actual" table or function is something we never actually deal with; we only deal with those reference-values. In other words, you don't get a copy of a table, you get a copy of a reference to a table.

If that's even more confusing, just forget I said that and I'll try to think of a better way to explain it.

Meaning: "-mainMenu|arcade|gameover" does not and it has to be part of the components list.

scissors61 wrote: ↑Fri Dec 23, 2016 2:51 amSomething I noticed using knife.system for a while, the - before aspects is helpful to omit a component from the arguments list but it doesn't work when several components are grouped to be optional with the pipe character |. Meaning: "-mainMenu|arcade|gameover" does not and it has to be part of the components list.

Zireael wrote: ↑Sat Feb 25, 2017 7:52 pm Does not what?

airstruck wrote: ↑Sat Feb 25, 2017 8:04 pm Sorry, I missed that. I'll take a look at it. You can report stuff like this in the issue tracker on github, I'll get it faster that way.