From TidalCycles userbase
listToPat :: [a] -> Pattern a
listToPat takes a list of things and turns them into a pattern where each item in the list becomes an event all happening in the same cycle, looping upon subsequent cycles.
d1 $ n (listToPat [0, 1, 2]) # s "superpiano"
is equivalent to
d1 $ n "[0 1 2]" # s "superpiano"
See also: fromList