minecraft safelyForward

local safelyForward = function()
    while turtle.detect() do
        if turtle.detectUp() then
          turtle.right()
          turtle.right()
          while turtle.detectUp() do
            while turtle.detect() do
              while turtle.detectDown() do
                turtle.back()
              end
              turtle.down()
            end
            turtle.forward()
          end
          turtle.right()
          turtle.right()
        end
        turtle.up()
      end
      turtle.forward()
      while not(turtle.detectDown()) do
        turtle.down()
      end
end