[Lua][Error] Loading in API with objects, how to use them?

API:

-- ninja_turtle.lua
ninja_turtle = {
current_position = {0, 0, 0},
rotation = 0,

-- __tostring = function (x) for i,v in pairs(x) do print(i, v) end
}


function ninja_turtle:new()
o = o or {}
setmetatable(o, self)
self.___index = self
return o
end

Code using the API:

-- doit
os.loadAPI("ninja_turtle.lua")
x = ninja_turtle:new{}
for i,v in pairs(x) do print (i, v) end

When running doit, I get this error: "doit:2: Attempt to index ? (a nil value)" which probably means that it can't find my ninja_turtle:new(), but why?

Thanks in advance,

You might need to remove the .lua extension from your API. If that doesn't work, make sure you're specifying the full path to it.

Nick, on 24 April 2012 - 04:46 AM said:

API:

-- ninja_turtle.lua
ninja_turtle = {
current_position = {0, 0, 0},
rotation = 0,

-- __tostring = function (x) for i,v in pairs(x) do print(i, v) end
}


function ninja_turtle:new()
o = o or {}
setmetatable(o, self)
self.___index = self
return o
end

Code using the API:

-- doit
os.loadAPI("ninja_turtle.lua")
x = ninja_turtle:new{}
for i,v in pairs(x) do print (i, v) end

When running doit, I get this error: "doit:2: Attempt to index ? (a nil value)" which probably means that it can't find my ninja_turtle:new(), but why?

Thanks in advance,

Like above remove the .lua extension,
Also the access the object it would be
ninja_turtle.ninja_turtle:new()
Because the file is in the global ninja_turtle variable
and then you ninja_turtle variable is inside that.

Thanks guys!

Second thought, why remove the .lua? Since when do extensions mess with files?

The problem with the extension is that the API is loaded by it's file name, so when you need to call it you do:

<apiname>.<function>()

When you put an extension to the filename you have to call it like:

<api>.<extension>.<function>

and lua would take it as trying to index the variable "api", wich doesn't exist.

If you want to keep the extension or name with dots, you would have to access like this:

_G["My.API.File.lua"].coolFunction()

tomass1996, on 30 April 2012 - 04:51 AM said:

If you want to keep the extension or name with dots, you would have to access like this:

_G["My.API.File.lua"].coolFunction()

That would work, but it's not really nice to do :)/>/>.
@Nick: If you want to keep the extension you will have to do what tomass says in the programs that use the API, it will work, but why would you do it when you can rename the API file.
This is just an opinion, do whatever you want, after all it's your code :)/>/>