* lisp/subr.el (with-demoted-errors): Add `format' argument.

* src/eval.c (Feval): Document the new use of `lexical'.

5 files changed, 48 insertions, 29 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 7da67efeadd..9914da31859 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -617,6 +617,9 @@ in the presence of files with negative time stamps.
 
 * Lisp Changes in Emacs 24.4
 
+** The second argument of `eval' can now be a lexical-environment.
+
+** `with-demoted-errors' takes an additional argument `format'.
 +++
 ** New function `define-error'.
 
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index fc73e563883..ff6ec4755b2 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2013-09-10  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * subr.el (with-demoted-errors): Add `format' argument.
+
 2013-09-10  Michael Albinus  <michael.albinus@gmx.de>
 
         * net/tramp.el (tramp-cleanup): Remove.  Functionality added to
@@ -10,11 +14,11 @@
         * net/tramp-adb.el (tramp-adb-maybe-open-connection):
         * net/tramp-sh.el (tramp-open-connection-setup-interactive-shell)
         (tramp-maybe-open-connection):
-        * net/tramp-smb.el (tramp-smb-maybe-open-connection): Use
-        `tramp-cleanup-connection'.
+        * net/tramp-smb.el (tramp-smb-maybe-open-connection):
+        Use `tramp-cleanup-connection'.
 
-        * net/tramp-sh.el (tramp-maybe-open-connection): Catch
-        'uname-changed inside the progress reporter.
+        * net/tramp-sh.el (tramp-maybe-open-connection):
+        Catch 'uname-changed inside the progress reporter.
 
 2013-09-10  Glenn Morris  <rgm@gnu.org>
 
@@ -34,15 +38,15 @@
 
         * net/tramp.el (tramp-find-method, tramp-find-user): Call `propertize'
         only if it is bound.  It isn't for XEmacs.
-        (with-tramp-progress-reporter): Do not let-bind `result'.  This
-        yields to scoping errors in XEmacs.
+        (with-tramp-progress-reporter): Do not let-bind `result'.
+        This yields to scoping errors in XEmacs.
         (tramp-handle-make-auto-save-file-name): New function, moved from
         tramp-sh.el.
 
         * net/tramp-adb.el (tramp-adb-file-name-handler-alist): Add handler
         for `make-auto-save-file-name'.
-        (tramp-adb--gnu-switches-to-ash): Use
-        `tramp-compat-replace-regexp-in-string'.
+        (tramp-adb--gnu-switches-to-ash):
+        Use `tramp-compat-replace-regexp-in-string'.
 
         * net/tramp-cache.el (tramp-cache-print): Call
         `substring-no-properties' only if it is bound.  It isn't for XEmacs.
@@ -50,8 +54,8 @@
         * net/tramp-cmds.el (tramp-bug): Call `propertize' only if it is
         bound.  It isn't for XEmacs.
 
-        * net/tramp-compat.el (tramp-compat-copy-file): Catch
-        `wrong-number-of-arguments' error.
+        * net/tramp-compat.el (tramp-compat-copy-file):
+        Catch `wrong-number-of-arguments' error.
         (tramp-compat-replace-regexp-in-string): New defun.
 
         * net/tramp-gvfs.el (tramp-gvfs-file-name-handler-alist): Add handler
@@ -62,21 +66,21 @@
         (tramp-gvfs-file-name): Use `tramp-compat-replace-regexp-in-string'.
         (tramp-synce-list-devices): Use `push' instead of `pushnew'.
 
-        * net/tramp-gw.el (tramp-gw-open-network-stream): Use
-        `tramp-compat-replace-regexp-in-string'.
+        * net/tramp-gw.el (tramp-gw-open-network-stream):
+        Use `tramp-compat-replace-regexp-in-string'.
 
-        * net/tramp-sh.el (tramp-sh-file-name-handler-alist): Call
-        `tramp-handle-make-auto-save-file-name'.
+        * net/tramp-sh.el (tramp-sh-file-name-handler-alist):
+        Call `tramp-handle-make-auto-save-file-name'.
         (tramp-sh-handle-make-auto-save-file-name): Move to tramp.el.
         (tramp-sh-file-gvfs-monitor-dir-process-filter)
-        (tramp-sh-file-inotifywait-process-filter): Use
-        `tramp-compat-replace-regexp-in-string'.
+        (tramp-sh-file-inotifywait-process-filter):
+        Use `tramp-compat-replace-regexp-in-string'.
         (tramp-compute-multi-hops): Use `push' instead of `pushnew'.
 
         * net/tramp-smb.el (tramp-smb-file-name-handler-alist): Add handler
         for `make-auto-save-file-name'.
-        (tramp-smb-handle-copy-directory): Call
-        `tramp-compat-replace-regexp-in-string'.
+        (tramp-smb-handle-copy-directory):
+        Call `tramp-compat-replace-regexp-in-string'.
         (tramp-smb-get-file-entries): Use `push' instead of `pushnew'.
         (tramp-smb-handle-copy-file): Improve error message.
         (tramp-smb-handle-rename-file): Rename directly only in case
@@ -95,8 +99,8 @@
         * progmodes/cc-langs.el (c-type-decl-suffix-key): Now matches ")"
         in Java Mode.
         (c-recognize-typeless-decls): Set the Java value to t.
-        * progmodes/cc-engine.el (c-forward-decl-or-cast-1): While
-        handling a "(", add a check for, effectively, Java, and handle a
+        * progmodes/cc-engine.el (c-forward-decl-or-cast-1):
+        While handling a "(", add a check for, effectively, Java, and handle a
         "typeless" declaration there.
 
 2013-09-07  Roland Winkler  <winkler@gnu.org>
diff --git a/lisp/subr.el b/lisp/subr.el
index 0a28d4778d4..de7c629b208 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -3350,16 +3350,22 @@ even if this catches the signal."
 (define-obsolete-function-alias 'condition-case-no-debug
   'condition-case-unless-debug "24.1")
 
-(defmacro with-demoted-errors (&rest body)
+(defmacro with-demoted-errors (format &rest body)
   "Run BODY and demote any errors to simple messages.
 If `debug-on-error' is non-nil, run BODY without catching its errors.
 This is to be used around code which is not expected to signal an error
-but which should be robust in the unexpected case that an error is signaled."
-  (declare (debug t) (indent 0))
-  (let ((err (make-symbol "err")))
+but which should be robust in the unexpected case that an error is signaled.
+For backward compatibility, if FORMAT is not a constant string, it
+is assumed to be part of BODY, in which case the message format
+used is \"Error: %S\"."
+  (declare (debug t) (indent 1))
+  (let ((err (make-symbol "err"))
+        (format (if (and (stringp format) body) format
+                  (prog1 "Error: %S"
+                    (if format (push format body))))))
     `(condition-case-unless-debug ,err
-         (progn ,@body)
-       (error (message "Error: %S" ,err) nil))))
+         ,(macroexp-progn body)
+       (error (message ,format ,err) nil))))
 
 (defmacro combine-after-change-calls (&rest body)
   "Execute BODY, but don't call the after-change functions till the end.
diff --git a/src/ChangeLog b/src/ChangeLog
index 4b688e43430..4e08178989e 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,7 @@
+2013-09-10  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * eval.c (Feval): Document the new use of `lexical'.
+
 2013-09-09  Dmitry Antipov  <dmantipov@yandex.ru>
 
         Review and drop old frame resize hack.
@@ -20,8 +24,8 @@
 2013-09-09  Dmitry Antipov  <dmantipov@yandex.ru>
 
         Cleanup frame flushing.
-        * dispextern.h (struct redisplay_interface): Drop
-        flush_display_optional because flush_display is enough
+        * dispextern.h (struct redisplay_interface):
+        Drop flush_display_optional because flush_display is enough
         for X and flushing via RIF is just a no-op for others.
         * frame.h (flush_frame): New function.
         * dispnew.c (update_frame):
diff --git a/src/eval.c b/src/eval.c
index 9db4d1fd81b..6e964f6604b 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -2033,7 +2033,9 @@ it is defines a macro.  */)
 
 DEFUN ("eval", Feval, Seval, 1, 2, 0,
        doc: /* Evaluate FORM and return its value.
-If LEXICAL is t, evaluate using lexical scoping.  */)
+If LEXICAL is t, evaluate using lexical scoping.
+LEXICAL can also be an actual lexical environment, in the form of an
+alist mapping symbols to their value.  */)
   (Lisp_Object form, Lisp_Object lexical)
 {
   ptrdiff_t count = SPECPDL_INDEX ();