Lua on boolean change event? -

so brainstorming programming, logic emulator in lua. have overhaul whole system, thought event based actions better constant update actions.

i have like:

local var1 = false local var2 = false while true   if key == "a"     var1 = not var1   end   if key == "s" var2 = not var2 end   var2 = var1 end 

but want this:

local var1 = false local var2 = false while true   if key == "a"     var1 = not var1   end   if key == "s" var2 = not var2 end   if on.change(var1)     var2 = var1   end end 

so yeah, want var2 independent, don't want keep setting var1, want var2 react var1, if var1 has changed.

if @ first code chunk, see cant control var2 independently, set var1, might set var1 short period of time.

if @ second code chunk, can see can control var2 independently var1, , have still react var1.

now analogous thing this:

local var1 = false local var2 = false while true   if key == "a"     var1 = not var1     var2 = var1   end   if key == "s"     var2 = not var2   end end 

but i'm afraid wouldn't possible implement, , slow down, since lot of loops going, adding more nested loops slow down...

so please post similar event on second code chunk, posted analogous one, hard implement, , there serious side effects, nested loops i'm doing.

thank time!

you can stuff metatables (pseudocode):

local mt = { __index = function(i,v)     if == "var1"          var1 = v         var2 = v     end end }  _g.setmetatable(mt) 

but i'd recommend google enough library automatically.