Multiple __index Metamethods in a Metatable?
So, I'm playing around with metatables, and on the Wiki, I learned this little trick:
local metatable= {
__index = {value= true}
}
local regulartable = setmetatable({}, metatable)
print(regulartable.value)
Prints "true" in the output.
I wanted to see if I could put multiple __index metamethods in the same metatable, so, in essence, I could have multiple pseudo "properties" of a table. I tried this:
local metatable= {
__index = {value= true},
__index = {secondvalue = false}
}
local regulartable = setmetatable({}, metatable)
print(regulartable.secondvalue, regulartable.value)
I noticed that with the second value set, the first value would be nil. I tried a few other things, but they all showed up as incorrect on the syntax checker, so they aren't worth mentioning here.
How do I set multiple __index metamethods in a single metatable?
2 answers
With a few more minutes of playing around, I discovered how to do it. (Funny how it works out.) Basically, you do this:
local metatable= {
__index = {value= true,
secondaryvalue = false}
}
local regulartable = setmetatable({}, metatable)
print(regulartable.value, regulartable.secondaryvalue)
This would print: true false
This means that there is no need for multiple __index metamethods in a metatable.
Minifig is correct, but the reason you can't set multiple __indexs is because the second definition replaces the first.
It's like trying to do this:
x = 1
x = 4
if x ~= 1 then
print("Broken!!!")
end