Question

In Lua, I have a tree relationship structure between objects where an object can have multiple children, but only one parent object, i.e.

obj—obj1—obj2—objd3—obj4—obj5—obj6

If I want to know obj6’s ‘distant’ parents instead of just the immediate parent obj5, how can I achieve that? I just need a list of parents two or more levels above the current object, and the API I’m working with only has a obj.parent property.

Pseudo-code would also be helpful to get me in the right direction.

Answer 1

Well, if your api supports .parent, can’t you do something like the following? I’m rusty with Lua but this should offer a start.

local function GetAncestors(child)

    local ancestors = {};

    if child.parent then
        local i = 0;
        ancestors[0] = child.parent;
        while ancestors[i].parent do
            ancestors[i + 1] = ancestors[i].parent;
            i = i + 1;
        end
    end

    return ancestors;

end