From b7e047fb96994980c4262f591299662e468af3c4 Mon Sep 17 00:00:00 2001 From: Miles Bader Date: Sat, 15 Jul 2000 14:59:26 +0000 Subject: [PATCH] (Fnext_single_char_property_change): Made a subr (was `next_single_char_property_change'). Do more error checking, and cleanup limit behavior. (Fprevious_single_char_property_change): New function. (syms_of_textprop): Initialize new subrs. --- src/textprop.c | 117 +++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 99 insertions(+), 18 deletions(-) diff --git a/src/textprop.c b/src/textprop.c index e53d77825f..8160aaa6ec 100644 --- a/src/textprop.c +++ b/src/textprop.c @@ -676,24 +676,29 @@ past position LIMIT; return LIMIT if nothing is found before LIMIT.") } -/* Value is the position in OBJECT after POS where the value of - property PROP changes. OBJECT must be a string or buffer. If - OBJECT is nil, use the current buffer. LIMIT if not nil limits the - search. */ - -Lisp_Object -next_single_char_property_change (pos, prop, object, limit) - Lisp_Object prop, pos, object, limit; +DEFUN ("next-single-char-property-change", Fnext_single_char_property_change, + Snext_single_char_property_change, 2, 4, 0, + "Return the position of next text property or overlay change for a specific property.\n\ +Scans characters forward from POSITION till it finds\n\ +a change in the PROP property, then returns the position of the change.\n\ +The optional third argument OBJECT is the string or buffer to scan.\n\ +The property values are compared with `eq'.\n\ +Return nil if the property is constant all the way to the end of OBJECT.\n\ +If the value is non-nil, it is a position greater than POSITION, never equal.\n\n\ +If the optional fourth argument LIMIT is non-nil, don't search\n\ +past position LIMIT; return LIMIT if nothing is found before LIMIT.") + (position, prop, object, limit) + Lisp_Object prop, position, object, limit; { if (STRINGP (object)) { - pos = Fnext_single_property_change (pos, prop, object, limit); - if (NILP (pos)) + position = Fnext_single_property_change (position, prop, object, limit); + if (NILP (position)) { if (NILP (limit)) - pos = make_number (XSTRING (object)->size); + position = make_number (XSTRING (object)->size); else - pos = limit; + position = limit; } } else @@ -701,7 +706,7 @@ next_single_char_property_change (pos, prop, object, limit) Lisp_Object initial_value, value; int count = specpdl_ptr - specpdl; - if (!NILP (object)) + if (! NILP (object)) CHECK_BUFFER (object, 0); if (BUFFERP (object) && current_buffer != XBUFFER (object)) @@ -710,12 +715,22 @@ next_single_char_property_change (pos, prop, object, limit) Fset_buffer (object); } - initial_value = Fget_char_property (pos, prop, object); + initial_value = Fget_char_property (position, prop, object); - while (XFASTINT (pos) < XFASTINT (limit)) + if (NILP (limit)) + XSETFASTINT (limit, BUF_ZV (current_buffer)); + else + CHECK_NUMBER_COERCE_MARKER (limit, 0); + + for (;;) { - pos = Fnext_char_property_change (pos, limit); - value = Fget_char_property (pos, prop, object); + position = Fnext_char_property_change (position, limit); + if (XFASTINT (position) >= XFASTINT (limit)) { + position = limit; + break; + } + + value = Fget_char_property (position, prop, object); if (!EQ (value, initial_value)) break; } @@ -723,10 +738,74 @@ next_single_char_property_change (pos, prop, object, limit) unbind_to (count, Qnil); } - return pos; + return position; } +DEFUN ("previous-single-char-property-change", + Fprevious_single_char_property_change, + Sprevious_single_char_property_change, 2, 4, 0, + "Return the position of previous text property or overlay change for a specific property.\n\ +Scans characters backward from POSITION till it finds\n\ +a change in the PROP property, then returns the position of the change.\n\ +The optional third argument OBJECT is the string or buffer to scan.\n\ +The property values are compared with `eq'.\n\ +Return nil if the property is constant all the way to the start of OBJECT.\n\ +If the value is non-nil, it is a position less than POSITION, never equal.\n\n\ +If the optional fourth argument LIMIT is non-nil, don't search\n\ +back past position LIMIT; return LIMIT if nothing is found before LIMIT.") + (position, prop, object, limit) + Lisp_Object prop, position, object, limit; +{ + if (STRINGP (object)) + { + position = Fprevious_single_property_change (position, prop, object, limit); + if (NILP (position)) + { + if (NILP (limit)) + position = make_number (XSTRING (object)->size); + else + position = limit; + } + } + else + { + Lisp_Object initial_value, value; + int count = specpdl_ptr - specpdl; + + if (! NILP (object)) + CHECK_BUFFER (object, 0); + + if (BUFFERP (object) && current_buffer != XBUFFER (object)) + { + record_unwind_protect (Fset_buffer, Fcurrent_buffer ()); + Fset_buffer (object); + } + + if (NILP (limit)) + XSETFASTINT (limit, BUF_BEGV (current_buffer)); + else + CHECK_NUMBER_COERCE_MARKER (limit, 0); + + initial_value = Fget_char_property (position, prop, object); + + for (;;) + { + position = Fprevious_char_property_change (position, limit); + if (XFASTINT (position) <= XFASTINT (limit)) { + position = limit; + break; + } + value = Fget_char_property (position - 1, prop, object); + if (!EQ (value, initial_value)) + break; + } + + unbind_to (count, Qnil); + } + + return position; +} DEFUN ("next-property-change", Fnext_property_change, Snext_property_change, 1, 3, 0, @@ -1892,6 +1971,8 @@ rear-nonsticky properties of the character overrides NONSTICKINESS."); defsubr (&Sget_char_property); defsubr (&Snext_char_property_change); defsubr (&Sprevious_char_property_change); + defsubr (&Snext_single_char_property_change); + defsubr (&Sprevious_single_char_property_change); defsubr (&Snext_property_change); defsubr (&Snext_single_property_change); defsubr (&Sprevious_property_change); -- 2.20.1