How to use multiple lua files?

[cybercircuit]

How do you use multiple lua files in a game? I mean, I know how to create them but I dont know how to use them.

P.S Is something like a class possible? And if so is it possible to use polymorphisim, and how?

[Eamonn]

As far as I'm aware, classes do not exist in Lua. There are, however, objects(or table ). For LÖVE, you do not need classes anyway. Lua is a true OOP language, using only objects for things. Like for example:

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love.graphics.print("Example.", 50, 50)

does the following:

1) Go into the love object
2) Look for the graphics object
3) Use the print() function in the graphics object which is inside the love object

Hope this all makes sense

To use a file after you've created it, you do

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require("filename")

or

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require "filename"

Hope this helps!

[bartbes]

Even though classes aren't built into lua, they can easily be implemented with tables, and there's quite a few class libraries for lua floating around on the internet.

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require("filename")
require "filename"

I'd like to note those are completely equivalent. (And require isn't special, this is a syntax feature available for every function.)
Apart from that, require doesn't take file names, it takes module names, which are closely related to file names, generally, to go from a file name to a module name you follow these steps:

1. Get the filename, for example: a/b/c.lua
2. Remove the extension: a/b/c
3. Replace slashes with dots: a.b.c

Therefore, to load a file at a/b/c.lua you'd run require("a.b.c").

[cybercircuit]

Thanks but that dident explain to me exactly how to use multiple lua files

[cybercircuit]

Even though classes aren't built into lua, they can easily be implemented with tables, and there's quite a few class libraries for lua floating around on the internet.

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require("filename")
require "filename"

I'd like to note those are completely equivalent. (And require isn't special, this is a syntax feature available for every function.)
Apart from that, require doesn't take file names, it takes module names, which are closely related to file names, generally, to go from a file name to a module name you follow these steps:

1. Get the filename, for example: a/b/c.lua
2. Remove the extension: a/b/c
3. Replace slashes with dots: a.b.c

Therefore, to load a file at a/b/c.lua you'd run require("a.b.c").

oh thx

[veethree]

What exactly don't you understand?

[cybercircuit]

How to call functions and variables from other files

[Larsii30]

Let's say you have a directory on your desktop with this in it :
- main.lua
- other.lua

The "other.lua" only contains the variable text = "Hello World".
now to load the "other.lua" you simple use require( "other" ).
This should be done on top of your main.lua or inside the love.load()
now you can access the var "text" from your main.

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require( "other" )

function love.draw()
  love.graphics.print( text, 10, 10 )
end

The same for functions. If you got this in your other.lua :

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function doMath( v1, v2 )
 return v1 + v2 
end

you can call it from your main .. like this :

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require( "other" )

function love.draw()
  love.graphics.print( text, 10, 10 ) -- "Hello World"
  love.graphics.print( doMath( 1, 1 ), 10, 30 ) -- display "2"
end

[cybercircuit]

Thanks a ton! Now I can make a game!

[veethree]

Also worth noting if in other.lua you put local in front of the text variable it would no longer be accessible in main.lua. Same goes for functions.

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local text = "Hello World".

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local function doMath( v1, v2 )
 return v1 + v2
end

If a variable or function isn't used outside of the file it's in, It's considered good practice to make it local.