bug#3752: 23.0.95; I can not understant a sentence in Intro to Emacs Lisp .

[Glenn Morris]

waterloo wrote:

> when test of while is nil , it does not run `print' following it.
> who  does print nil ?
>
> or  if all function will print its return value ?

As explained in the earlier section of the manual (on "Evaluation"),
evaluating a function with C-x C-e prints the return value. For example

(+ 2 2)

or

(progn
  (princ "Evaluating with C-x C-e prints the return value.\n")
  42)