Using modules that return two instances of a class

[interested_party]

I'm running into an issue that really is throwing me for a loop. My code is ugly and I'll only share some snippets to give the general issue clarity. This is for basic card game mechanics. I have a class that defines a Hand, and the module returns two instances of this class (player1Hand and player2Hand).

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local Class = require("hump.class")
local love = require("love")

local hand = Class{
    init = function(self)
        self.x = 0
        self.y = 760
        self.width = 1920
        self.length = 320
        self.cards = {}
        self.numCards = 0
    end
}

local player1Hand = hand()
local player2Hand = hand()
player2Hand.y = 0

return player1Hand, player2Hand

There are some methods in this class as well but I've omitted them as they are not the source of my issue. What I can't figure out is that when I require these Hands in my gamestate, player1Hand works perfectly normal as intended, but if I copy the exact same code and sub player2Hand in it throws the error "attempt to index upvalue "player2Hand" (a nil value).

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local player1Hand, player2Hand = require("Elements/Hand")

function play:update()
    player1.x, player1.y = love.mouse.getPosition()
    for i = 1, player1Hand.numCards do
        player1Hand.cards[i]:isHovered(player1.x, player1.y)
        player1Hand.cards[i]:move(player1.x, player1.y)

    end
    --for i = 1, player2Hand.numCards do
    --player2Hand.cards[i]:isHovered(player1.x, player1.y)
    --player2Hand.cards[i]:move(player1.x, player1.y)

    --end
end

Again I've omitted a lot of irrelevant code. When the lower for loop is commented out, the program runs fine. But it throws that error when it's included. I'm at a loss because both instances of the Hand class are identical and are implemented the same way.

[interested_party]

I am an idiot. Sorry I posted this before taking adequate time to think about it. Just realized that a module can't return multiple values unless they are in a table. Simple fix, just return the two hands in a table and extract them into local variables in the gamestate module. If anyone is as dumb as me there is your answer.

[pgimeno]

Modules typically define classes. Returning instances is somewhat ugly.

Anyway, a long time ago, I was told a trick to return multiple values from a module: return a function that returns these values. In your case, it would involve replacing the last line with this:

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return function() return player1Hand, player2Hand end

and instead of just require("Elements/Hand"), you'd add an extra couple parens to invoke the function:

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local player1Hand, player2Hand = require("Elements/Hand")()

[interested_party]

Ah that makes even more sense than a table solution. Appreciate it! I'm definitely still learning the do's and don't's!