pp package is great for pretty-printing Emacs Lisp forms, but can be excruciatingly slow for "large" forms.
Is there a general rule-of-thumb for determining whether we should
pp a form or not? E.g. if a sequence contains more than X elements,
pp would probably be unbearably slow?
I'm not sure what causes the poor performance of
pp for "large" forms; that is, I'm not sure what a good definition of "large" is. Is it length? Depth? Some combination of both? What dominates