Shitty Bugs thread

Post here whenever you waste hours of your life on a simple bug, so that others may mock you (and/or learn from your mistakes).

(cons 'let (cons paramlist body)) is not the same as (list 'let paramlist body)

[[0]*n]*m does not initialize an m rows by n columns matrix (at least not one that will work like you think it should).

use [[0 for j in range(n)] for i in range(m)] instead