Lua local question

[tentus]

In Kurosuke, I require "scenes" from the main file, the first of which has this line in it:

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require "subclass/startup"

This startup file has tons of variable like this in it:

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currentLevel = "level_1"
multiplayer = 1
players = {}

Most of these variables don't get mentioned again until we're two more scenes into the game (ie, two more requires deep).

If a variable is not defined as local, it is global to the entire game. It doesn't matter which file it is defined in. Think in terms of functions, not files.

Edit: following statement is false, apparently.
So, if you want a variable to be local to a file, you have to make sure that file's contents are inside a big function, otherwise it is effectively global again (it's effectively local will refer to the whole program, if I remember correctly).

[T-Bone]

Okay, I get it

[Robin]

So, if you want a variable to be local to a file, you have to make sure that file's contents are inside a big function, otherwise it is effectively global again (it's effectively local will refer to the whole program, if I remember correctly).

No.

Lua is fully lexically scoped, which means that:

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local this = true
for i = 1, 1 do
   local this = false
   print(this) -- prints false
end
print(this) -- prints true

A file is compiled down to a "chunk", just like functions are.
If you have a file called a.lua:

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local jazz = 5

And a main.lua:

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require 'a'
print(jazz) -- prints nil

[tentus]

So, if you want a variable to be local to a file, you have to make sure that file's contents are inside a big function, otherwise it is effectively global again (it's effectively local will refer to the whole program, if I remember correctly).

No.

Lua is fully lexically scoped, which means that:

Code: Select all

local this = true
for i = 1, 1 do
   local this = false
   print(this) -- prints false
end
print(this) -- prints true

A file is compiled down to a "chunk", just like functions are.
If you have a file called a.lua:

Code: Select all

local jazz = 5

And a main.lua:

Code: Select all

require 'a'
print(jazz) -- prints nil

Huh. I don't recall that behavior, but I guess that shows how little I use inter-file variables that don't need to be global.