diff options
Diffstat (limited to 'src/eval.c')
| -rw-r--r-- | src/eval.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/eval.c b/src/eval.c index 57a273cd4aa..32b9d366fc3 100644 --- a/src/eval.c +++ b/src/eval.c @@ -475,6 +475,14 @@ usage: (setq [SYM VAL]...) */) DEFUN ("quote", Fquote, Squote, 1, UNEVALLED, 0, doc: /* Return the argument, without evaluating it. `(quote x)' yields `x'. +Warning: `quote' does not construct its return value, but just returns +the value that was pre-constructed by the Lisp reader (see info node +`(elisp)Printed Representation'). +This means that '(a . b) is not identical to (cons 'a 'b): the former +does not cons. Quoting should be reserved for constants that will +never be modified by side-effects, unless you like self-modifying code. +See the common pitfall in info node `(elisp)Rearrangement' for an example +of unexpected results when a quoted object is modified. usage: (quote ARG) */) (Lisp_Object args) { |