back 1.0 bk 1.0

back number

The turtle moves backward by number steps. (If numberis negative, the turtle moves forward.)

Turtles using this primitive can move a maximum of one unit per time increment. So bk 0.5 and bk 1 both take one unit of time, but bk 3 takes three.

If the turtle cannot move backward number steps because it is not permitted by the current topology the turtle will complete as many steps of 1 as it can and stop.

See also forward, jump, can-move?.