ruby - Many nested `for` cycles depending on a variable -

i want put many for cycles in themselfs depending of value in variable.
example, if variable @var = 1, need perform:

for letter1 in @range   end 

if variable @var = 2:

for letter1 in @range   letter2 in @range       end end  

if variable @var = 3

for letter1 in @range   letter2 in @range     letter3 in @range           end   end end  

is there smarter/less code way code below? don't wanna repeat myself on again.

if @var == 1   letter2 in @range       end elsif @var == 2   letter1 in @range     letter2 in @range           end   end elsif @var == 3   letter1 in @range     letter2 in @range       letter3 in @range               end     end   end  end 

that do something part same in each case. difference how cycles in.

you should read recursion: http://en.wikipedia.org/wiki/recursion_(computer_science)
like:

def f(depth,letters=[])   if depth == 0     someting letters   else     letter in @range       f(depth-1,letters+[letter])     end   end end  f(@var) 

f function, goes through letter calling again recursively. each call have info depth, means, how more deep recursion should be.