Reduce regexp usage, now CL-oriented non-regexp code available, core Lisp lisp/ChangeLog addition: 2015-04-01 Aidan Kehoe <kehoea@parhasard.net> When calling #'string-match with a REGEXP without regular expression special characters, call #'search, #'mismatch, #'find, etc. instead, making our code less likely to side-effect other functions' match data and a little faster. * apropos.el (apropos-command): * apropos.el (apropos): Call (position ?\n ...) rather than (string-match "\n" ...) here. * buff-menu.el: * buff-menu.el (buffers-menu-omit-invisible-buffers): Don't fire up the regexp engine just to check if a string starts with a space. * buff-menu.el (select-buffers-tab-buffers-by-mode): Don't fire up the regexp engine just to compare mode basenames. * buff-menu.el (format-buffers-tab-line): * buff-menu.el (build-buffers-tab-internal): Moved to being a label within the following. * buff-menu.el (buffers-tab-items): Use the label. * bytecomp.el (byte-compile-log-1): Don't fire up the regexp engine just to look for a newline. * cus-edit.el (get): Ditto. * cus-edit.el (custom-variable-value-create): Ditto, but for a colon. * descr-text.el (describe-text-sexp): Ditto. * descr-text.el (describe-char-unicode-data): Use #'split-string-by-char given that we're just looking for a semicolon. * descr-text.el (describe-char): Don't fire up the regexp engine just to look for a newline. * disass.el (disassemble-internal): Ditto. * files.el (file-name-sans-extension): Implement this using #'position. * files.el (file-name-extension): Correct this function's docstring, implement it in terms of #'position. * files.el (insert-directory): Don't fire up the regexp engine to split a string by space; don't reverse the list of switches, this is actually a longstand bug as far as I can see. * gnuserv.el (gnuserv-process-filter): Use #'position here, instead of consing inside #'split-string needlessly. * gtk-file-dialog.el (gtk-file-dialog-update-dropdown): Use #'split-string-by-char here, don't fire up #'split-string for directory-sep-char. * gtk-font-menu.el (hack-font-truename): Implement this more cheaply in terms of #'find, #'split-string-by-char, #'equal, rather than #'string-match, #'split-string, #'string-equal. * hyper-apropos.el (hyper-apropos-grok-functions): * hyper-apropos.el (hyper-apropos-grok-variables): Look for a newline using #'position rather than #'string-match in these functions. * info.el (Info-insert-dir): * info.el (Info-insert-file-contents): * info.el (Info-follow-reference): * info.el (Info-extract-menu-node-name): * info.el (Info-menu): Look for fixed strings using #'position or #'search as appropriate in this file. * ldap.el (ldap-decode-string): * ldap.el (ldap-encode-string): #'encode-coding-string, #'decode-coding-string are always available, don't check if they're fboundp. * ldap.el (ldap-decode-address): * ldap.el (ldap-encode-address): Use #'split-string-by-char in these functions. * lisp-mnt.el (lm-creation-date): * lisp-mnt.el (lm-last-modified-date): Don't fire up the regexp engine just to look for spaces in this file. * menubar-items.el (default-menubar): Use (not (mismatch ...)) rather than #'string-match here, for simple regexp. Use (search "beta" ...) rather than (string-match "beta" ...) * menubar-items.el (sort-buffers-menu-alphabetically): * menubar-items.el (sort-buffers-menu-by-mode-then-alphabetically): * menubar-items.el (group-buffers-menu-by-mode-then-alphabetically): Don't fire up the regexp engine to check if a string starts with a space or an asterisk. Use the more fine-grained results of #'compare-strings; compare case-insensitively for the buffer menu. * menubar-items.el (list-all-buffers): * menubar-items.el (tutorials-menu-filter): Use #'equal rather than #'string-equal, which, in this context, has the drawback of not having a bytecode, and no redeeming features. * minibuf.el: * minibuf.el (un-substitute-in-file-name): Use #'count, rather than counting the occurences of $ using the regexp engine. * minibuf.el (read-file-name-internal-1): Don't fire up the regexp engine to search for ?=. * mouse.el (mouse-eval-sexp): Check for newline with #'find. * msw-font-menu.el (mswindows-reset-device-font-menus): Split a string by newline with #'split-string-by-char. * mule/japanese.el: * mule/japanese.el ("Japanese"): Use #'search rather than #'string-match; canoncase before comparing; fix a bug I had introduced where I had been making case insensitive comparisons where the case mattered. * mule/korea-util.el (default-korean-keyboard): Look for ?3 using #'find, not #'string-march. * mule/korea-util.el (quail-hangul-switch-hanja): Search for a fixed string using #'search. * mule/mule-cmds.el (set-locale-for-language-environment): #'position, #'substitute rather than #'string-match, #'replace-in-string. * newcomment.el (comment-make-extra-lines): Use #'search rather than #'string-match for a simple string. * package-get.el (package-get-remote-filename): Use #'position when looking for ?@ * process.el (setenv): * process.el (read-envvar-name): Use #'position when looking for ?=. * replace.el (map-query-replace-regexp): Use #'split-string-by-char instead of using an inline implementation of it. * select.el (select-convert-from-cf-text): * select.el (select-convert-from-cf-unicodetext): Use #'position rather than #'string-match in these functions. * setup-paths.el (paths-emacs-data-root-p): Use #'search when looking for simple string. * sound.el (load-sound-file): Use #'split-string-by-char rather than an inline reimplementation of same. * startup.el (splash-screen-window-body): * startup.el (splash-screen-tty-body): Search for simple strings using #'search. * version.el (emacs-version): Ditto. * x-font-menu.el (hack-font-truename): Implement this more cheaply in terms of #'find, #'split-string-by-char, #'equal, rather than #'string-match, #'split-string, #'string-equal. * x-font-menu.el (x-reset-device-font-menus-core): Use #'split-string-by-char here. * x-init.el (x-initialize-keyboard): Search for a simple string using #'search.

@c -*-texinfo-*-
@c This is part of the XEmacs Lisp Reference Manual.
@c Copyright (C) 1998 Oliver Graf <ograf@fga.de>
@c Original reference is (c) 1990, 1991, 1992, 1993, 1994 Free Software Foundation, Inc.
@c See the file lispref.texi for copying conditions.
@setfilename ../../info/dragndrop.texi
@node Drag and Drop, Modes, Scrollbars, Top
@chapter Drag and Drop
@cindex drag and drop

@emph{WARNING}: the Drag'n'Drop API is still under development and the
interface may change! The current implementation is considered experimental.

  Drag'n'drop is a way to transfer information between multiple applications.
To do this several GUIs define their own protocols. Examples are CDE, Motif,
KDE, MSWindows, GNOME, and many more. To catch all these protocols, XEmacs
provides a generic API.

One prime idea behind the API is to use a data interface that is
transparent for all systems. The author thinks that this is best
archived by using URL and MIME data, cause any internet enabled system
must support these for email already. XEmacs also already provides
powerful interfaces to support these types of data (tm and w3).

@menu
* Supported Protocols:: Which low-level protocols are supported.
* Drop Interface::      How XEmacs handles a drop from another application.
* Drag Interface::      Calls to initiate a drag from XEmacs.
@end menu

@node Supported Protocols
@section Supported Protocols

The current release of XEmacs only support a small set of Drag'n'drop
protocols. Some of these only support limited options available in the API.

@menu
* CDE dt::              Common Desktop Environment used on suns.
* MSWindows OLE::       Mr. Gates way of live.
* Loose ends::          The other protocols.
@end menu

@node CDE dt
@subsection CDE dt
@cindex CDE dt

CDE stands for Common Desktop Environment. It is based on the Motif
widget library. It's drag'n'drop protocol is also an abstraction of the
Motif protocol (so it might be possible, that XEmacs will also support
the Motif protocol soon).

CDE has three different types: file, buffer, and text. XEmacs only uses
file and buffer drags. The API will disallow full URL drags, only file
method URLs are passed through.

Buffer drags are always converted to plain text.

@node MSWindows OLE
@subsection MSWindows OLE
@cindex MSWindows OLE

Only allows file drags and drops.

@node Loose ends
@subsection Loose ends

The following protocols will be supported soon: Xdnd, Motif, Xde (if I
get some specs).

In particular Xdnd will be one of the protocols that can benefit from
the XEmacs API, cause it also uses MIME types to encode dragged data.

@node Drop Interface
@section Drop Interface
@cindex drop
@cindex Drop API

For each activated low-level protocol, an internal routine will catch
incoming drops and convert them to a dragdrop-drop type
misc-user-event.

This misc-user-event has its function argument set to
@code{dragdrop-drop-dispatch} and the object contains the data of the drop
(converted to URL/MIME specific data). This function will search the variable
@code{experimental-dragdrop-drop-functions} for a function that can handle the
dropped data.

To modify the drop behavior, the user can modify the variable
@code{experimental-dragdrop-drop-functions}. Each element of this list
specifies a possible handler for dropped data. The first one that can handle
the data will return @code{t} and exit. Another possibility is to set a
extent-property with the same name. Extents are checked prior to the
variable.

The customization group @code{drag-n-drop} shows all variables of user
interest.

@node Drag Interface
@section Drag Interface
@cindex drag
@cindex Drag API

This describes the drag API (not implemented yet).