[COMMIT] Fill out docstrings fo `function,' `quote' and `require.'

[Aidan Kehoe]

APPROVE COMMIT 

NOTE: This patch has been committed.

src/ChangeLog addition:

2007-01-20  Aidan Kehoe  <kehoea at parhasard.net>

	* eval.c:
	Document in more detail what happens with byte-compilation,
	`function', and `quote'. 
	* fns.c:
	Mention that `require' is evaluated both at byte-compile time and
	at runtime. 


XEmacs Trunk source patch:
Diff command:   cvs -q diff -Nu
Files affected: src/fns.c
===================================================================
RCS src/eval.c
===================================================================
RCS

Index: src/eval.c
===================================================================
RCS file: /pack/xemacscvs/XEmacs/xemacs/src/eval.c,v
retrieving revision 1.93
diff -u -u -r1.93 eval.c
--- src/eval.c	2006/08/29 14:10:54	1.93
+++ src/eval.c	2007/01/20 16:51:06
@@ -1177,6 +1177,15 @@
 
 DEFUN ("quote", Fquote, 1, UNEVALLED, 0, /*
 Return the argument, without evaluating it.  `(quote x)' yields `x'.
+
+There is an alternative and more used reader syntax for `quote'.  Precede
+any Lisp object with a single apostrophe, and that Lisp object will be
+returned unevaluated. 'x is thus equivalent to (quote x).
+
+Do not use `quote' or the single apostrophe for lambda expressions that you
+would prefer to be byte-compiled.  Use `function', which see, or take
+advantage of the fact that lambda expressions are self-quoting and such
+lambda expressions will be automatically byte-compiled.
 */
        (args))
 {
@@ -1185,8 +1194,16 @@
 
 DEFUN ("function", Ffunction, 1, UNEVALLED, 0, /*
 Like `quote', but preferred for objects which are functions.
-In byte compilation, `function' causes its argument to be compiled.
-`quote' cannot do that.
+
+As with `quote' there is an alternative reader syntax for `function' which
+in practice is used more often.  Writing #'OBJECT is equivalent to writing
+\(function OBJECT), where OBJECT is some Lisp object.
+
+In byte compilation, `function' causes a lambda expression argument to be
+compiled.  `quote' cannot do that.  lambda expressions are, however,
+self-quoting, and self-quoted lambda expressions will be byte-compiled.
+Only lambda expressions explicitly quoted with `quote' or that occur in
+nested data lists will not be byte-compiled.
 */
        (args))
 {
Index: src/fns.c
===================================================================
RCS file: /pack/xemacscvs/XEmacs/xemacs/src/fns.c,v
retrieving revision 1.64
diff -u -u -r1.64 fns.c
--- src/fns.c	2005/10/25 11:16:24	1.64
+++ src/fns.c	2007/01/20 16:51:08
@@ -3582,6 +3582,13 @@
 If FILENAME is omitted, the printname of FEATURE is used as the file name.
 If optional third argument NOERROR is non-nil, then return nil if the file
 is not found instead of signaling an error.
+Normally the return value is FEATURE.
+The normal messages at start and end of loading FILENAME are suppressed.
+
+In order to make it possible for a required package to provide macros to be
+expanded at byte-compilation time, top level calls of `require' are
+evaluated both at byte-compile time and at run time.  That is, any top-level
+call to `require' is wrapped in an implicit \(eval-and-compile ...\) block.
 */
        (feature, filename, noerror))
 {

-- 
When I was in the scouts, the leader told me to pitch a tent. I couldn't
find any pitch, so I used creosote.