3 replies to this topic

[Macapple]

Hi there,players
I've got a problem,i want my turtle to go forward a SPECIFIED (x) number of times...
I tried it like this

--Program name is: Forward ..x..
a = x
while a > 0 do
turtle.forward()
a = a-1
end

It says: Attempt to compare nil with number

How to fix this? />

[xuma202]

The argument passed into the program you'll have to use arg[1] you can then name the program however you want but you don't need a ..x... at the end

forward

a = arg[1]
while a > 0 do
turtle.forward()
a = a-1
end

[MysticT]

You need to get the arguments first:

local args = { ... }

That will give you an array (wich is actually a table with numeric indices) with all the arguments passed to the program. Now you can access them like:

local times = args[1]

but remember that the arguments are strings, so you have to convert it if you need a number:

local nTimes = tonumber(args[1])

And now you can use it in a loop (I'll use a for loop since it's better for this kind of things):

for i = 1, nTimes do
  turtle.forward()
end

[Macapple]

MysticT, on 12 July 2012 - 01:52 PM, said:

You need to get the arguments first:

local args = { ... }

That will give you an array (wich is actually a table with numeric indices) with all the arguments passed to the program. Now you can access them like:

local times = args[1]

but remember that the arguments are strings, so you have to convert it if you need a number:

local nTimes = tonumber(args[1])

And now you can use it in a loop (I'll use a for loop since it's better for this kind of things):

for i = 1, nTimes do
  turtle.forward()
end

Thank You so much,it worked fine />