Recursive Function Problems

Hi, I'm working on a program, where I need it to recursivelly call itself at times; the problem is that by calling it all the variables get reset and dont work anymore, coming from other languages this stumped me.

So, how could I go about using a loop counter, calling the function from inside itself and upon returning have the values set back to where they should be?

Please post your current code.

you can initialize variables outside of the function. I imagine your code looks something like this:

local function foo()
   a =1
   b = 2
   do something to a and b
   recursive call
end

But if you make the variables global, they will retain their states and not get reset. Like so:

local	a =1
local	b = 2
local function foo()
   do something to a and b
   recursive call
end

Of course, I could be totally wrong. Code would be nice to see, like Lyqyd said.

Basically this

function runProgram(program, loops)
        if program[1] == "set" then
                table.remove(program, 1)
                program["NAME"] = program[1]
                table.remove(program, 1)

        elseif program["NAME"] then

        else
                program["NAME"] = "MAIN"
        end

print("\nExecuting: ", program["NAME"], " of length ", #program, ", ", loops, " times")
        while loops > 0 do
                loops = loops - 1

                program["COUNT"] = 0
                depth = 0
                while program["COUNT"] < #program do
                        program["COUNT"] = program["COUNT"] + 1
print(" ", program["NAME"], " >[count] ", program["COUNT"], " ( ", program[program["COUNT"]], " )")
                        if type(program[program["COUNT"]]) == "table" then
                                if tonumber(program[program["COUNT"] + 1]) then
                                        runProgram(program[program["COUNT"]], tonumber(program[program["COUNT"] + 1]))
                                        program["COUNT"] = program["COUNT"] + 1
                                else
                                        runProgram(program[program["COUNT"]], 1)
                                end

                        elseif program[program["COUNT"]] == "(" then
                                depth = depth + 1
                                program[program["COUNT"]] = {}

                                if program[program["COUNT"] + 1] == "set" then
                                        table.insert(program[program["COUNT"]], table.remove(program, program["COUNT"]+1))
                                        program[program["COUNT"]]["NAME"] = program[program["COUNT"] + 1] .. program["NAME"]
                                        table.insert(program[program["COUNT"]], table.remove(program, program["COUNT"] + 1))

                                else
                                        table.insert(program[program["COUNT"]], "set")
                                        table.insert(program[program["COUNT"]], program["NAME"] .. " >] " .. tostring(program["COUNT"]))
                                end

--print("\nNew SubProgram: ", program[program["COUNT"]]["NAME"])
--print("DEPTH: ", depth)

                                while depth ~= 0 and program["COUNT"] < #program do
                                        if program[program["COUNT"] + 1] == "(" then
                                                depth = depth + 1
                                                table.insert(program[program["COUNT"]], table.remove(program, program["COUNT"] + 1))
--print("DEPTH: ", depth)

                                        elseif program[program["COUNT"] + 1] == ")" then
                                                depth = depth - 1
--print("DEPTH: ", depth)
                                                if depth == 0 then
                                                        table.remove(program, program["COUNT"] + 1)

                                                else
                                                        table.insert(program[program["COUNT"]], table.remove(program, program["COUNT"] + 1))
                                                end

                                        else
                                                table.insert(program[program["COUNT"]], table.remove(program, program["COUNT"] + 1))
                                        end
                                end

                                if tonumber(program[program["COUNT"] + 1]) then
                                        program[program["COUNT"]] = runProgram(program[program["COUNT"]], tonumber(program[program["COUNT"] + 1]))
                                        program["COUNT"] = program["COUNT"] + 1
                                else
                                        program[program["COUNT"]] = runProgram(program[program["COUNT"]], 1)
                                end

                        elseif program[program["COUNT"]] == ")" then
                                print("\n\nFound \")\" when not in a sub-program, maybe missing a space at \"(\"?")
                                break

                        elseif APIList["API"][program[program["COUNT"]]] then
                                if tonumber(program[program["COUNT"] + 1]) then
                                        program["COUNT"] = program["COUNT"] + 1
print("    ", program["NAME"], " [-", program[program["COUNT"]], "-> ", APIList["NAME"], ".", program[program["COUNT"]-1], "()")
                                        for i=1,tonumber(program[program["COUNT"]]) do
                                                APIList["API"][program[program["COUNT"]-1]]()
                                        end

                                else
print(program["NAME"], " [-> ", APIList["NAME"], ".", program[program["COUNT"]], "()")
                                        APIList["API"][program[program["COUNT"]]]()
                                end

                        elseif tonumber(program[program["COUNT"]]) then
print("\tNumber: ", program[program["COUNT"]])

                        else
                                os.run( {}, tostring(program[program["COUNT"]]))
                        end
--os.pullEvent( "key" )
                end
        end

        program["COUNT"] = nil
        return program

end

I found a way to make it work, by using the fact that it's a table to my advantage, but was honestly not expecting the variables to do such a thing.

Bluemanduck, on 10 March 2015 - 07:12 AM said:

you can initialize variables outside of the function. I imagine your code looks something like this:

local function foo()
   a =1
   b = 2
   do something to a and b
   recursive call
end

But if you make the variables global, they will retain their states and not get reset. Like so:

local	a =1
local	b = 2
local function foo()
   do something to a and b
   recursive call
end

Of course, I could be totally wrong. Code would be nice to see, like Lyqyd said.

You are not wrong, but the problem was that I needed a fresh set of the variables each call, that would then return to their old value after the call, like c++ and such, but found a way to make it work, as mentioned, thanks anyways!

Hah! I vastly underestimated what you were talking about. Glad you fixed it, that looks like a hot mess.

Bluemanduck, on 10 March 2015 - 08:43 AM said:

Hah! I vastly underestimated what you were talking about. Glad you fixed it, that looks like a hot mess.

Heh yup, planning on making it a full on language if time permits, quite a project for my first delve into lua, but quite fun!