How do I clone a table

[Ranguna259]

I'd like to know a way to clone tables.
Whenver I try to do

Code: Select all

table2=table1

and change data inside table 2, that same data will change in table1.

I've thought of using serialization libs to serialize a table and then load the string into the new table but mayber there's another way ..?

[jangsy5]

Code: Select all

a = {1,2,3}
b = {}

for k, v in ipairs(a) do
    b[k] = v
end

Pretty much means instead of b referring to a, b has a table that refers to the same values as a. Which is kind of cloning right? Well this is the best I can think of. You have to note that it'll reference values that are tables so you need to clone those too, probably using if statement to check.

[davisdude]

*Made by Robin

Code: Select all

function DeepCopy( Table, Cache ) -- Makes a deep copy of a table. 
    if type( Table ) ~= 'table' then
        return Table
    end

    Cache = Cache or {}
    if Cache[Table] then
        return Cache[Table]
    end

    local New = {}
    Cache[Table] = New
    for Key, Value in pairs( Table ) do
        New[DeepCopy( Key, Cache)] = DeepCopy( Value, Cache )
    end

    return New
end

[Ranguna259]

You have to note that it'll reference values that are tables so you need to clone those too, probably using if statement to check.

I'd already thought of that but, as you said, tables within tables are the problem and if checks would not be the solution, but apparently Robin found a way.(or someone else did because I think I've seen his solution somewhere else)

*Made by Robin

Code: Select all

function DeepCopy( Table, Cache ) -- Makes a deep copy of a table. 
    if type( Table ) ~= 'table' then
        return Table
    end

    Cache = Cache or {}
    if Cache[Table] then
        return Cache[Table]
    end

    local New = {}
    Cache[Table] = New
    for Key, Value in pairs( Table ) do
        New[DeepCopy( Key, Cache)] = DeepCopy( Value, Cache )
    end

    return New
end

Thank you very much for sharing, and thank you Robin for coding this