Lisp form print depth

Question

What controls the print depth of lisp forms? For example:

(macroexpand '(defun foo () (let ((bar)) (+ 1 2))))

becomes

(defalias (quote foo) (function (lambda nil (let ... ...))))

in the *Messages* buffer.

Answer 1

Print length/depth for the echo area are in eval-expression-print-length and eval-expresssion-print-depth respectively.

For general printing (e.g. princ), the relevant variables are print-length and print-level.