(Python - Keyboard module) What am i doing wrong here! when I press up, I expect the mapping to press e but it presses q for up, down and for left

Question

I'm trying to suppress keypresses and remap them to some other keys. The code looks something like this:

from time import sleep
import keyboard
import os

os.chdir(os.path.dirname(__file__))

keys = {
    'up':'e',
    'down':'s',
    'left':'q'
}

for each in zip(keys.keys(), keys.values()):
    keyboard.on_press_key(each[0], lambda _:keyboard.press(each[1]), True)
    keyboard.on_release_key(each[0], lambda _:keyboard.release(each[1]), True)


while not keyboard.is_pressed('shift'):
    sleep(0.5)

But when I run this thing, I expect to get key press of 'e' key when I press up, 's' when I press down and 'q' only when I press left key, But I'm getting 'q' key press for all these three remapped keys!. What am I doing wrong here?!

score 0 · Answer 1 · answered Jul 08 '22 at 00:28

This happens because of mechanics how python functions bind values and arguments. So you define three callbacks, each of them uses "q" letter. And please, don't zip(keys.keys(), keys.values()) - although since python 3.7 it is probably safe, it is weird.

from time import sleep
import keyboard

keys = {
    'up': 'e',
    'down': 's',
    'left': 'q',
}

for orig, repl in keys.items():
    keyboard.on_press_key(orig, (lambda _, repl=repl: keyboard.press(repl)), True)
    keyboard.on_release_key(orig, (lambda _, repl=repl: keyboard.release(repl)), True)

while not keyboard.is_pressed('shift'):
    sleep(0.5)

(Python - Keyboard module) What am i doing wrong here! when I press up, I expect the mapping to press e but it presses q for up, down and for left

1 Answers1