emacs-29 419b4d44914: ; Improve documentation of with-restriction

[Gregory Heytings]

branch: emacs-29
commit 419b4d44914701cedf308df58c3e5789715c87e7
Author: Gregory Heytings <gregory@heytings.org>
Commit: Gregory Heytings <gregory@heytings.org>

    ; Improve documentation of with-restriction
    
    * lisp/subr.el (with-restriction):
    * doc/lispref/positions.texi (Narrowing): Make it clear that the
    argument is evaluated and that the result of the evaluation must
    not be nil.
---
 doc/lispref/positions.texi |  3 ++-
 lisp/subr.el               | 15 +++++++--------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/doc/lispref/positions.texi b/doc/lispref/positions.texi
index e74a165b9ed..3d769bfe78a 100644
--- a/doc/lispref/positions.texi
+++ b/doc/lispref/positions.texi
@@ -1169,7 +1169,8 @@ saved bounds.  In that case it is equivalent to
 
 @cindex labeled narrowing
 @cindex labeled restriction
-When the optional argument @var{label}, a symbol, is present, the
+When the optional argument @var{label}, which is evaluated to get the
+label to use and must yield a non-@code{nil} value, is present, the
 narrowing is @dfn{labeled}.  A labeled narrowing differs from a
 non-labeled one in several ways:
 
diff --git a/lisp/subr.el b/lisp/subr.el
index 0b397b7bebf..43cf4572fe2 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -3964,11 +3964,11 @@ See also `locate-user-emacs-file'.")
 
 The current restrictions, if any, are restored upon return.
 
-When the optional :label LABEL argument is present, in which
-LABEL is a symbol, inside BODY, `narrow-to-region' and `widen'
-can be used only within the START and END limits.  To gain access
-to other portions of the buffer, use `without-restriction' with the
-same LABEL argument.
+When the optional LABEL argument, which is evaluated to get the
+label to use and must yield a non-nil value, is present, inside
+BODY, `narrow-to-region' and `widen' can be used only within the
+START and END limits.  To gain access to other portions of the
+buffer, use `without-restriction' with the same LABEL argument.
 
 \(fn START END [:label LABEL] BODY)"
   (declare (indent 2) (debug t))
@@ -3990,9 +3990,8 @@ same LABEL argument.
 
 The current restrictions, if any, are restored upon return.
 
-When the optional :label LABEL argument is present, the
-restrictions set by `with-restriction' with the same LABEL argument
-are lifted.
+When the optional LABEL argument is present, the restrictions set
+by `with-restriction' with the same LABEL argument are lifted.
 
 \(fn [:label LABEL] BODY)"
   (declare (indent 0) (debug t))