Wait so what does the local function do?

Hey Typical,

Local allows things to be defined in a different scope. In programming, a scope defines accessibility. Everything in your script is inside of a scope, and the variables which you address all depend on the scope in which they are.

Local limits the scope of a variable and makes it only be defined in that local scope. While not declaring a variable as local will allow it to be accessible through the entire script. It is standard practice to declare pretty much all variables locally, as it can help preserve memory, and allows you to use this idea of scope as a feature.

Example: Local Variables

local a = 3

function sum(b, c) --Will return the sum of a, b, and c. a is in the bigger scope
    return a + b + c
end

function subtract(b) --Will return the difference between a and b
    return b-a
end

print(a + b + c) -- Will give you an error, something along the lines of performing arithmetic on nil

Now here, b and c are only within the scope of the function sum. Even though they are not defined as local, all parameters are within the scope of their respective functions.

However, a is defined within the scope of the entire function. That is why it can be used both within sum and subtract.

Essentially, local functions follow a similar rule:

Example: Local Functions

local function sum(a, b, c) -- Returns the sum of a, b, and c
    local function subtract(a, b) --Returns the difference between b and a.
        return b-a
    end

    subtract(2,1) -- Will run with no errors and returns -1

    return a + b + c
end

sum(1,2,3) -- Returns 6.

subtract(2, 1) -- Will error because subtract isn't a function defined in the bigger scope, but rather one defined within the scope of the function called sum.

Above is just an example of using local functions and both of the local functions are defined within their own scope. Keep in mind, the function sum can be accessed anywhere within the script, including within itself. That is more of the idea of recursion.

Here you can learn more about scope.

Best regards,

Idealist Developer