@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1990-1995, 1998-2012 Free Software Foundation, Inc.
+@c Copyright (C) 1990-1995, 1998-2013 Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@node Text
@chapter Text
@code{filter-buffer-substring-functions}, and returns the result. The
obsolete variable @code{buffer-substring-filters} is also consulted.
If both of these variables are @code{nil}, the value is the unaltered
-text from the buffer, i.e.@: what @code{buffer-substring} would
+text from the buffer, i.e., what @code{buffer-substring} would
return.
If @var{delete} is non-@code{nil}, this function deletes the text
@code{filter-buffer-substring}.
The first hook function is passed a @var{fun} that is equivalent to
-the default operation of @code{filter-buffer-substring}, i.e. it
+the default operation of @code{filter-buffer-substring}, i.e., it
returns the buffer-substring between @var{start} and @var{end}
(processed by any @code{buffer-substring-filters}) and optionally
deletes the original text from the buffer. In most cases, the hook
@node Yanking
@subsection Yanking
- Yanking means inserting text from the kill ring, but it does
-not insert the text blindly. Yank commands and some other commands
-use @code{insert-for-yank} to perform special processing on the
-text that they copy into the buffer.
+ Yanking means inserting text from the kill ring, but it does not
+insert the text blindly. The @code{yank} command, and related
+commands, use @code{insert-for-yank} to perform special processing on
+the text before it is inserted.
@defun insert-for-yank string
-This function normally works like @code{insert} except that it doesn't
-insert the text properties (@pxref{Text Properties}) in the list
-variable @code{yank-excluded-properties}. However, if any part of
-@var{string} has a non-@code{nil} @code{yank-handler} text property,
-that property can do various special processing on that part of the
-text being inserted.
+This function works like @code{insert}, except that it processes the
+text in @var{string} according to the @code{yank-handler} text
+property, as well as the variables @code{yank-handled-properties} and
+@code{yank-excluded-properties} (see below), before inserting the
+result into the current buffer.
@end defun
@defun insert-buffer-substring-as-yank buf &optional start end
-This function resembles @code{insert-buffer-substring} except that it
-doesn't insert the text properties in the
-@code{yank-excluded-properties} list.
+This function resembles @code{insert-buffer-substring}, except that it
+processes the text according to @code{yank-handled-properties} and
+@code{yank-excluded-properties}. (It does not handle the
+@code{yank-handler} property, which does not normally occur in buffer
+text anyway.)
@end defun
- You can put a @code{yank-handler} text property on all or part of
-the text to control how it will be inserted if it is yanked. The
-@code{insert-for-yank} function looks for that property. The property
-value must be a list of one to four elements, with the following
-format (where elements after the first may be omitted):
+ If you put a @code{yank-handler} text property on all or part of a
+string, that alters how @code{insert-for-yank} inserts the string. If
+different parts of the string have different @code{yank-handler}
+values (comparison being done with @code{eq}), each substring is
+handled separately. The property value must be a list of one to four
+elements, with the following format (where elements after the first
+may be omitted):
@example
(@var{function} @var{param} @var{noexclude} @var{undo})
@table @var
@item function
-When @var{function} is present and non-@code{nil}, it is called instead of
-@code{insert} to insert the string. @var{function} takes one
-argument---the string to insert.
+When @var{function} is non-@code{nil}, it is called instead of
+@code{insert} to insert the string, with one argument---the string to
+insert.
@item param
If @var{param} is present and non-@code{nil}, it replaces @var{string}
-(or the part of @var{string} being processed) as the object passed to
-@var{function} (or @code{insert}); for example, if @var{function} is
-@code{yank-rectangle}, @var{param} should be a list of strings to
-insert as a rectangle.
+(or the substring of @var{string} being processed) as the object
+passed to @var{function} (or @code{insert}). For example, if
+@var{function} is @code{yank-rectangle}, @var{param} should be a list
+of strings to insert as a rectangle.
@item noexclude
-If @var{noexclude} is present and non-@code{nil}, the normal removal of the
-yank-excluded-properties is not performed; instead @var{function} is
-responsible for removing those properties. This may be necessary
-if @var{function} adjusts point before or after inserting the object.
+If @var{noexclude} is present and non-@code{nil}, that disables the
+normal action of @code{yank-handled-properties} and
+@code{yank-excluded-properties} on the inserted string.
@item undo
If @var{undo} is present and non-@code{nil}, it is a function that will be
@end table
@cindex yanking and text properties
+@defopt yank-handled-properties
+This variable specifies special text property handling conditions for
+yanked text. It takes effect after the text has been inserted (either
+normally, or via the @code{yank-handler} property), and prior to
+@code{yank-excluded-properties} taking effect.
+
+The value should be an alist of elements @code{(@var{prop}
+. @var{fun})}. Each alist element is handled in order. The inserted
+text is scanned for stretches of text having text properties @code{eq}
+to @var{prop}; for each such stretch, @var{fun} is called with three
+arguments: the value of the property, and the start and end positions
+of the text.
+@end defopt
+
@defopt yank-excluded-properties
-Yanking discards certain text properties from the yanked text, as
-described above. The value of this variable is the list of properties
-to discard. Its default value contains properties that might lead to
-annoying results, such as causing the text to respond to the mouse or
-specifying key bindings.
+The value of this variable is the list of properties to remove from
+inserted text. Its default value contains properties that might lead
+to annoying results, such as causing the text to respond to the mouse
+or specifying key bindings. It takes effect after
+@code{yank-handled-properties}.
@end defopt
+
@node Yank Commands
@subsection Functions for Yanking
positive, point was at the beginning of the deleted text, otherwise it
was at the end.
-@item (t @var{high} . @var{low})
+@item (t @var{sec-high} @var{sec-low} @var{microsec} @var{picosec})
This kind of element indicates that an unmodified buffer became
-modified. The elements @var{high} and @var{low} are two integers, each
-recording 16 bits of the visited file's modification time as of when it
-was previously visited or saved. @code{primitive-undo} uses those
+modified. The list @code{(@var{sec-high} @var{sec-low} @var{microsec}
+@var{picosec})} represents the visited file's modification time as of
+when it was previously visited or saved, using the same format as
+@code{current-time}; see @ref{Time of Day}. @code{primitive-undo} uses those
values to determine whether to mark the buffer as unmodified once again;
it does so only if the file's modification time matches those numbers.
@item face
@cindex face codes of text
@kindex face @r{(text property)}
-The @code{face} property controls the appearance of the character,
-such as its font and color. @xref{Faces}. The value of the property
-can be the following:
+The @code{face} property controls the appearance of the character
+(@pxref{Faces}). The value of the property can be the following:
@itemize @bullet
@item
A face name (a symbol or string).
@item
-A property list of face attributes. This has the form (@var{keyword}
-@var{value} @dots{}), where each @var{keyword} is a face attribute
-name and @var{value} is a meaningful value for that attribute. With
-this feature, you do not need to create a face each time you want to
-specify a particular attribute for certain text.
+An anonymous face: a property list of the form @code{(@var{keyword}
+@var{value} @dots{})}, where each @var{keyword} is a face attribute
+name and @var{value} is a value for that attribute.
@item
-A list of faces. This specifies a face which is an aggregate of the
+A list of faces. Each list element should be either a face name or an
+anonymous face. This specifies a face which is an aggregate of the
attributes of each of the listed faces. Faces occurring earlier in
-the list have higher priority. Each list element must have one of the
-two above forms (i.e.@: either a face name or a property list of face
-attributes).
+the list have higher priority.
+
+@item
+A cons cell of the form @code{(foreground-color . @var{color-name})}
+or @code{(background-color . @var{color-name})}. This specifies the
+foreground or background color, similar to @code{(:foreground
+@var{color-name})} or @code{(:background @var{color-name})}. This
+form is supported for backward compatibility only, and should be
+avoided.
@end itemize
Font Lock mode (@pxref{Font Lock Mode}) works in most buffers by
@code{mouse-face} property value.
Emacs ignores all face attributes from the @code{mouse-face} property
-that alter the text size (e.g. @code{:height}, @code{:weight}, and
+that alter the text size (e.g., @code{:height}, @code{:weight}, and
@code{:slant}). Those attributes are always the same as for the
unhighlighted text.
@deffn Command base64-encode-region beg end &optional no-line-break
This function converts the region from @var{beg} to @var{end} into base
64 code. It returns the length of the encoded text. An error is
-signaled if a character in the region is multibyte, i.e.@: in a
+signaled if a character in the region is multibyte, i.e., in a
multibyte buffer the region must contain only characters from the
charsets @code{ascii}, @code{eight-bit-control} and
@code{eight-bit-graphic}.
Emacs has built-in support for computing @dfn{cryptographic hashes}.
A cryptographic hash, or @dfn{checksum}, is a digital ``fingerprint''
-of a piece of data (e.g.@: a block of text) which can be used to check
+of a piece of data (e.g., a block of text) which can be used to check
that you have an unaltered copy of that data.
@cindex message digest
SHA-1, SHA-2, SHA-224, SHA-256, SHA-384 and SHA-512. MD5 is the
oldest of these algorithms, and is commonly used in @dfn{message
digests} to check the integrity of messages transmitted over a
-network. MD5 is not ``collision resistant'' (i.e.@: it is possible to
+network. MD5 is not ``collision resistant'' (i.e., it is possible to
deliberately design different pieces of data which have the same MD5
hash), so you should not used it for anything security-related. A
similar theoretical weakness also exists in SHA-1. Therefore, for
modification. Each function receives three arguments: the beginning
and end of the region just changed, and the length of the text that
existed before the change. All three arguments are integers. The
-buffer has been changed is always the current buffer.
+buffer that has been changed is always the current buffer.
The length of the old text is the difference between the buffer
positions before and after that text as it was before the change. As