lua interpreter, having to import file twice for full functionality

Question

so i have a lua file analogous to this:

x = { __index = x}

constructor = function()
    local o = {}
    return setmetatable(o,x)
end

function x:print()
    print("hello world")
end

i type the following into the interpretr:

dofile "file.lua"
a = constructor()
a:print() --error attempt to call method 'print' (a nil value)

dofile "file.lua"
a = constructor()
a:print() -- hello world

the method works the second time i import the file but not the first. why is this? I have tried changing the order (putting the constructor function last) and it was the same.

score 3 · Answer 1 · answered Oct 11 '13 at 00:02

3

The first time x is nil. It gets defined and then used the second time.

You need to write x = {}; x.__index = x.

answered Oct 11 '13 at 00:02

lhf

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lua interpreter, having to import file twice for full functionality

1 Answers1