Attempt to index local (a boolean value)

Question

I have 2 different Lua files, main.lua and game_model.lua. I'm trying to save some details in a JSON file (I googled that using a JSON file would be the best way to save a user's settings and score), but I'm getting the following error:

Error: File: main.lua Line: 11 Attempt to index local 'game' (a boolean value)

Why is am I getting this error and how can fix it?

Here is the code in my main.lua:

--Main.lua

display.setStatusBar( display.HiddenStatusBar )

local composer = require( "composer" )
local game = require("data.game_model")

myGameSettings = {}
myGameSettings.highScore = 1000
myGameSettings.soundOn = true
myGameSettings.musicOff = true
myGameSettings.playerName = "Andrian Gungon"
game.saveTable(myGameSettings, "mygamesettings.json")

composer.gotoScene("scripts.menu")

game_model.lua (in the data subdirectory) contains this code:

--game_model.lua (located at data/game_model.lua)

local json = require("json")

function saveTable(t, filename)
    local path = system.pathForFile( filename, system.DocumentsDirectory)
    local file = io.open(path, "w")
    if (file) then
        local contents = json.encode(t)
        file:write( contents )
        io.close( file )
        return true
    else
        print( "Error!" )
        return false
    end
end

function loadTable(filename)
    local path = system.pathForFile( filename, system.DocumentsDirectory)
    local contents = ""
    local myTable = {}
    local file = io.open( path, "r" )
    if (file) then         
         local contents = file:read( "*a" )
         myTable = json.decode(contents);
         io.close( file )
         return myTable 
    end
    return nil
end

Answer 1

It means that the module data.game_model did not return anything when it was loaded.
In this case, require returns true.