From: Stefan Monnier Date: Fri, 14 May 2010 17:53:42 +0000 (-0400) Subject: * eval.c (specbind): Disallow let-binding frame-local vars. X-Git-Tag: emacs-pretest-24.0.90~104^2~275^2~438^2~208^2~70 X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=4e2db1fe4be382f540f175316f3608fe4a9a93ae;p=emacs.git * eval.c (specbind): Disallow let-binding frame-local vars. Remove left-over duplicate test. Add comment. --- diff --git a/etc/NEWS b/etc/NEWS index b2a213c8fa2..a60962cf1f4 100644 --- a/etc/NEWS +++ b/etc/NEWS @@ -221,6 +221,7 @@ Secret Service API requires D-Bus for communication. * Lisp changes in Emacs 24.1 +** frame-local variables cannot be let-bound any more. ** prog-mode is a new major-mode meant to be the parent of programming mode. ** define-minor-mode accepts a new keyword :variable. diff --git a/src/ChangeLog b/src/ChangeLog index 14311049a17..f258174625a 100644 --- a/src/ChangeLog +++ b/src/ChangeLog @@ -1,3 +1,8 @@ +2010-05-14 Stefan Monnier + + * eval.c (specbind): Remove left-over duplicate test. + Disallow let-binding frame-local vars. Add comment. + 2010-05-14 Eli Zaretskii Make the cache of bidi iterator states dynamically allocated. @@ -5,7 +10,7 @@ (bidi_init_it): Call it. (bidi_cache_iterator_state): Enlarge the cache if needed. - * bidi.c (bidi_move_to_visually_next): Renamed from + * bidi.c (bidi_move_to_visually_next): Rename from bidi_get_next_char_visually. All callers changed. 2010-05-14 Kenichi Handa @@ -18,8 +23,8 @@ Set CMP_IT->reversed_p. (composition_update_it): Pay attention to CMP_IT->reversed_p. - * xdisp.c (set_iterator_to_next): Call - composition_compute_stop_pos with negative ENDPOS if we are + * xdisp.c (set_iterator_to_next): + Call composition_compute_stop_pos with negative ENDPOS if we are scanning backward. Call composition_compute_stop_pos if scan direction is changed. (next_element_from_buffer): Call composition_compute_stop_pos with diff --git a/src/eval.c b/src/eval.c index 2a0330acc38..199c4705736 100644 --- a/src/eval.c +++ b/src/eval.c @@ -3308,6 +3308,21 @@ grow_specpdl () specpdl_ptr = specpdl + count; } +/* specpdl_ptr->symbol is a field which describes which variable is + let-bound, so it can be properly undone when we unbind_to. + It can have the following two shapes: + - SYMBOL : if it's a plain symbol, it means that we have let-bound + a symbol that is not buffer-local (at least at the time + the let binding started). Note also that it should not be + aliased (i.e. when let-binding V1 that's aliased to V2, we want + to record V2 here). + - (SYMBOL WHERE . BUFFER) : this means that it is a let-binding for + variable SYMBOL which can be buffer-local. WHERE tells us + which buffer is affected (or nil if the let-binding affects the + global value of the variable) and BUFFER tells us which buffer was + current (i.e. if WHERE is non-nil, then BUFFER==WHERE, otherwise + BUFFER did not yet have a buffer-local value). */ + void specbind (symbol, value) Lisp_Object symbol, value; @@ -3339,7 +3354,10 @@ specbind (symbol, value) set_internal (symbol, value, Qnil, 1); break; } - case SYMBOL_LOCALIZED: case SYMBOL_FORWARDED: + case SYMBOL_LOCALIZED: + if (SYMBOL_BLV (sym)->frame_local) + error ("Frame-local vars cannot be let-bound"); + case SYMBOL_FORWARDED: { Lisp_Object ovalue = find_symbol_value (symbol); specpdl_ptr->func = 0; @@ -3376,6 +3394,7 @@ specbind (symbol, value) /* FIXME: The third value `current_buffer' is only used in let_shadows_buffer_binding_p which is itself only used in set_internal for local_if_set. */ + eassert (NILP (where) || EQ (where, cur_buf)); specpdl_ptr->symbol = Fcons (symbol, Fcons (where, cur_buf)); /* If SYMBOL is a per-buffer variable which doesn't have a @@ -3460,13 +3479,10 @@ unbind_to (count, value) Fset_default (symbol, this_binding.old_value); /* If `where' is non-nil, reset the value in the appropriate local binding, but only if that binding still exists. */ - else if (BUFFERP (where)) - { - if (BUFFERP (where) - ? !NILP (Flocal_variable_p (symbol, where)) - : !NILP (Fassq (symbol, XFRAME (where)->param_alist))) - set_internal (symbol, this_binding.old_value, where, 1); - } + else if (BUFFERP (where) + ? !NILP (Flocal_variable_p (symbol, where)) + : !NILP (Fassq (symbol, XFRAME (where)->param_alist))) + set_internal (symbol, this_binding.old_value, where, 1); } /* If variable has a trivial value (no forwarding), we can just set it. No need to check for constant symbols here,