Ḣ
and Ṫ
modify their arguments
Æ
prefix and Œ
prefix come from CJam's m
and e
prefixes), and CJam (and Golfscript) both had (
and )
acting on arrays. )
on an array [1, 2, 3, 4, 5]
pushes 1
and [2, 3, 4, 5]
to the stack (and (
pushed [1, 2, 3, 4], 5
to the stack), i.e. modifying head/tail