robot

robot.py

# Original
# 16 lines

from gpiozero import RyanteckRobot, Button
from signal import pause

robot = RyanteckRobot()

left = Button(26)
right = Button(16)
fw = Button(21)
bw = Button(20)

fw.when_pressed = robot.forward
fw.when_released = robot.stop

left.when_pressed = robot.left
left.when_released = robot.stop

right.when_pressed = robot.right
right.when_released = robot.stop

bw.when_pressed = robot.backward
bw.when_released = robot.stop

pause()

robot2.py

# Zip approach
# 8 lines

from gpiozero import RyanteckRobot, Button
from signal import pause

robot = RyanteckRobot()

buttons = [Button(btn) for btn in [26, 16, 21, 20]]
actions = [robot.forward, robot.left, robot.right, robot.backward]

for btn, act in zip(directions, actions): btn.when_pressed = act

for btn in [fw, left, right, bw]: btn.when_released = robot.stop

pause()

robot3.py

# Zip approach with shortened object names
# 8 lines

from gpiozero import RyanteckRobot as R, Button as B
import signal as s

r = R()

b = [B(n) for n in [26, 16, 21, 20]]
a = [r.forward, r.left, r.right, r.backward]

for d, c in zip(b, a): d.when_pressed = c

for n in b: n.when_released = r.stop

s.pause()

robot4.py

# Dictionary approach
# 13 lines

from gpiozero import RyanteckRobot, Button
from signal import pause

robot = RyanteckRobot()

button_actions = {
    Button(26): robot.forward,
    Button(16): robot.left,
    Button(21): robot.right,
    Button(20): robot.backward,
}

for btn, action in button_actions.items():
    btn.when_pressed = action
    btn.when_released = robot.stop

pause()

robot5.py

# Dictionary approach with one very ling line
# 5 lines

from gpiozero import RyanteckRobot, Button
import signal

robot = RyanteckRobot()

for btn, action in {Button(26): robot.forward, Button(16): robot.left, Button(21): robot.right, Button(20): robot.backward}.items(): btn.when_pressed, btn.when_released = action, robot.stop

pause()

robot6.py

# Dictionary approach with one-letter object names
# 5 lines

from gpiozero import RyanteckRobot as R, Button as B
import signal as s

r = R()

for b, a in {B(26): r.forward, B(16): r.left, B(21): r.right, B(20): r.backward}.items(): b.when_pressed, b.when_released = a, r.stop

s.pause()

Hmm, 5 and 6 are relying on hidden implementation to keep their Button references alive (in other words, if that hidden implementation changes, they'll break). A minimized version of 4 is about the best I can do off the top of my head, but I'll keep thinking about it!