path: root/Doc/Zsh/zle.yo

texinode(Zsh Line Editor)(Completion Widgets)(Shell Builtin Commands)(Top)
chapter(Zsh Line Editor)
cindex(line editor)
cindex(editor, line)
cindex(ZLE)
sect(Description)
pindex(ZLE, use of)
If the tt(ZLE) option is set (which it is by default in interactive shells)
and the shell input is attached to the terminal, the user
is able to edit command lines.

There are two display modes.  The first, multiline mode, is the
default.  It only works if the tt(TERM) parameter is set to a valid
terminal type that can move the cursor up.  The second, single line
mode, is used if tt(TERM) is invalid or incapable of moving the
cursor up, or if the tt(SINGLE_LINE_ZLE) option is set.
pindex(SINGLE_LINE_ZLE, use of)
cindex(ksh, editor mode)
cindex(editor ksh style)
This mode
is similar to bf(ksh), and uses no termcap sequences.  If tt(TERM) is
"emacs", the tt(ZLE) option will be unset by default.

vindex(BAUD, use of)
vindex(COLUMNS, use of)
vindex(LINES, use of)
The parameters tt(BAUD), tt(COLUMNS), and tt(LINES) are also used by the
line editor.
ifzman(See em(Parameters Used By The Shell) in zmanref(zshparam))\
ifnzman(noderef(Parameters Used By The Shell)).

The parameter tt(zle_highlight) is also used by the line editor;
ifzman(see em(Character Highlighting) below)\
ifnzman(noderef(Character Highlighting)).  Highlighting
of special characters and the region between the cursor and the
mark (as set with tt(set-mark-command) in Emacs mode) is enabled
by default; consult this reference for more information.  Irrascible
conservatives will wish to know that all highlighting may be disabled by
the following setting:

example(zle_highlight=(none))

startmenu()
menu(Keymaps)
menu(Zle Builtins)
menu(Zle Widgets)
menu(Character Highlighting)
endmenu()

texinode(Keymaps)(Zle Builtins)()(Zsh Line Editor)
sect(Keymaps)
cindex(keymaps)
cindex(key bindings)
cindex(bindings, key)
A keymap in ZLE contains a set of bindings between key sequences
and ZLE commands.  The empty key sequence cannot be bound.

There can be any number of keymaps at any time, and each keymap has one
or more names.  If all of a keymap's names are deleted, it disappears.
findex(bindkey, use of)
tt(bindkey) can be used to manipulate keymap names.

Initially, there are four keymaps:

startsitem()
sitem(tt(emacs))(EMACS emulation)
sitem(tt(viins))(vi emulation - insert mode)
sitem(tt(vicmd))(vi emulation - command mode)
sitem(tt(.safe))(fallback keymap)
endsitem()

The `tt(.safe)' keymap is special.  It can never be altered, and the name
can never be removed.  However, it can be linked to other names, which can
be removed.  In the future other special keymaps may be added; users should
avoid using names beginning with `tt(.)' for their own keymaps.

vindex(VISUAL)
vindex(EDITOR)
In addition to these four names, either `tt(emacs)' or `tt(viins)' is
also linked to the name `tt(main)'.  If one of the tt(VISUAL) or
tt(EDITOR) environment variables contain the string `tt(vi)' when the shell
starts up then it will be `tt(viins)', otherwise it will be `tt(emacs)'.
tt(bindkey)'s tt(-e) and tt(-v)
options provide a convenient way to override this default choice.

When the editor starts up, it will select the `tt(main)' keymap.
If that keymap doesn't exist, it will use `tt(.safe)' instead.

In the `tt(.safe)' keymap, each single key is bound to tt(self-insert),
except for ^J (line feed) and ^M (return) which are bound to tt(accept-line).
This is deliberately not pleasant to use; if you are using it, it
means you deleted the main keymap, and you should put it back.
subsect(Reading Commands)
When ZLE is reading a command from the terminal, it may read a sequence
that is bound to some command and is also a prefix of a longer bound string.
In this case ZLE will wait a certain time to see if more characters
are typed, and if not (or they don't match any longer string) it will
execute the binding.  This timeout is defined by the tt(KEYTIMEOUT) parameter;
its default is 0.4 sec.  There is no timeout if the prefix string is not
itself bound to a command.

The key timeout is also applied when ZLE is reading the bytes from a
multibyte character string when it is in the appropriate mode.  (This
requires that the shell was compiled with multibyte mode enabled; typically
also the locale has characters with the UTF-8 encoding, although any
multibyte encoding known to the operating system is supported.)  If the
second or a subsequent byte is not read within the timeout period, the
shell acts as if tt(?) were typed and resets the input state.

As well as ZLE commands, key sequences can be bound to other strings, by using
`tt(bindkey -s)'.
When such a sequence is read, the replacement string is pushed back as input,
and the command reading process starts again using these fake keystrokes.
This input can itself invoke further replacement strings, but in order to
detect loops the process will be stopped if there are twenty such replacements
without a real command being read.

A key sequence typed by the user can be turned into a command name for use
in user-defined widgets with the tt(read-command) widget, described
ifzman(below)\
ifnzman(in noderef(Miscellaneous) below)\
.

texinode(Zle Builtins)(Zle Widgets)(Keymaps)(Zsh Line Editor)
sect(Zle Builtins)
cindex(zle, builtin commands)
The ZLE module contains three related builtin commands. The tt(bindkey)
command manipulates keymaps and key bindings; the tt(vared) command invokes
ZLE on the value of a shell parameter; and the tt(zle) command manipulates
editing widgets and allows command line access to ZLE commands from within
shell functions.

startitem()
findex(bindkey)
cindex(keys, rebinding)
cindex(rebinding keys)
cindex(keys, binding)
cindex(binding keys)
cindex(keymaps)
xitem(tt(bindkey) [ var(options) ] tt(-l))
xitem(tt(bindkey) [ var(options) ] tt(-d))
xitem(tt(bindkey) [ var(options) ] tt(-D) var(keymap) ...)
xitem(tt(bindkey) [ var(options) ] tt(-A) var(old-keymap new-keymap))
xitem(tt(bindkey) [ var(options) ] tt(-N) var(new-keymap) [ var(old-keymap) ])
xitem(tt(bindkey) [ var(options) ] tt(-m))
xitem(tt(bindkey) [ var(options) ] tt(-r) var(in-string) ...)
xitem(tt(bindkey) [ var(options) ] tt(-s) var(in-string out-string) ...)
xitem(tt(bindkey) [ var(options) ] var(in-string command) ...)
item(tt(bindkey) [ var(options) ] [ var(in-string) ])(
tt(bindkey)'s options can be divided into three categories: keymap selection,
operation selection, and others.  The keymap selection options are:

startitem()
item(tt(-e))(
Selects keymap `tt(emacs)', and also links it to `tt(main)'.
)
item(tt(-v))(
Selects keymap `tt(viins)', and also links it to `tt(main)'.
)
item(tt(-a))(
Selects keymap `tt(vicmd)'.
)
item(tt(-M) var(keymap))(
The var(keymap) specifies a keymap name.
)
enditem()

If a keymap selection is required and none of the options above are used, the
`tt(main)' keymap is used.  Some operations do not permit a keymap to be
selected, namely:

startitem()
item(tt(-l))(
List all existing keymap names.  If the tt(-L)
option is also used, list in the form of tt(bindkey)
commands to create the keymaps.
)
item(tt(-d))(
Delete all existing keymaps and reset to the default state.
)
item(tt(-D) var(keymap) ...)(
Delete the named var(keymap)s.
)
item(tt(-A) var(old-keymap new-keymap))(
Make the var(new-keymap) name an alias for var(old-keymap), so that
both names refer to the same keymap.  The names have equal standing;
if either is deleted, the other remains.  If there is already a keymap
with the var(new-keymap) name, it is deleted.
)
item(tt(-N) var(new-keymap) [ var(old-keymap) ])(
Create a new keymap, named var(new-keymap).  If a keymap already has that
name, it is deleted.  If an var(old-keymap) name is given, the new keymap
is initialized to be a duplicate of it, otherwise the new keymap will
be empty.
)
enditem()

To use a newly created keymap, it should be linked to tt(main).  Hence
the sequence of commands to create and use a new keymap `tt(mymap)'
initialized from the tt(emacs) keymap (which remains unchanged) is:

example(bindkey -N mymap emacs
bindkey -A mymap main)

Note that while `tt(bindkey -A) var(newmap) tt(main)' will work when
var(newmap) is tt(emacs) or tt(viins), it will not work for tt(vicmd), as
switching from vi insert to command mode becomes impossible.

The following operations act on the `tt(main)' keymap if no keymap
selection option was given:

startitem()
item(tt(-m))(
Add the built-in set of meta-key bindings to the selected keymap.
Only keys that are unbound or bound to tt(self-insert) are affected.
)
item(tt(-r) var(in-string) ...)(
Unbind the specified var(in-string)s in the selected keymap.
This is exactly equivalent to binding the strings to tt(undefined-key).

When tt(-R) is also used, interpret the var(in-string)s as ranges.

When tt(-p) is also used, the var(in-string)s specify prefixes.  Any
binding that has the given var(in-string) as a prefix, not including the
binding for the var(in-string) itself, if any, will be removed.  For
example,

example(bindkey -rpM viins '^[')

will remove all bindings in the vi-insert keymap beginning with an escape
character (probably cursor keys), but leave the binding for the escape
character itself (probably tt(vi-cmd-mode)).  This is incompatible with the
option tt(-R).
)
item(tt(-s) var(in-string out-string) ...)(
Bind each var(in-string) to each var(out-string).
When var(in-string) is typed, var(out-string) will be
pushed back and treated as input to the line editor.
When tt(-R) is also used, interpret the var(in-string)s as ranges.
)
item(var(in-string command) ...)(
Bind each var(in-string) to each var(command).
When tt(-R) is used, interpret the var(in-string)s as ranges.
)
item([ var(in-string) ])(
List key bindings.  If an var(in-string) is specified, the binding of
that string in the selected keymap is displayed.  Otherwise, all key
bindings in the selected keymap are displayed.  (As a special case,
if the tt(-e) or tt(-v) option is used alone, the keymap is em(not)
displayed - the implicit linking of keymaps is the only thing that
happens.)

When the option tt(-p) is used, the var(in-string) must be present.
The listing shows all bindings which have the given key sequence as a
prefix, not including any bindings for the key sequence itself.

When the tt(-L) option is used, the list is in the form of tt(bindkey)
commands to create the key bindings.
)
enditem()

When the tt(-R) option is used as noted above, a valid range consists of
two characters, with an optional `tt(-)' between them.  All characters
between the two specified, inclusive, are bound as specified.

For either var(in-string) or var(out-string), the following
escape sequences are recognised:

startsitem()
sitem(tt(\a))(bell character)
sitem(tt(\b))(backspace)
sitem(tt(\e), tt(\E))(escape)
sitem(tt(\f))(form feed)
sitem(tt(\n))(linefeed (newline))
sitem(tt(\r))(carriage return)
sitem(tt(\t))(horizontal tab)
sitem(tt(\v))(vertical tab)
sitem(tt(\)var(NNN))(character code in octal)
sitem(tt(\x)var(NN))(character code in hexadecimal)
sitem(tt(\M)[tt(-)]var(X))(character with meta bit set)
sitem(tt(\C)[tt(-)]var(X))(control character)
sitem(tt(^)var(X))(control character)
endsitem()

In all other cases, `tt(\)' escapes the following character.  Delete is
written as `tt(^?)'.  Note that `tt(\M^?)' and `tt(^\M?)' are not the same,
and that (unlike emacs), the bindings `tt(\M-)var(X)' and `tt(\e)var(X)'
are entirely distinct, although they are initialized to the same bindings
by `tt(bindkey -m)'.
)
findex(vared)
cindex(parameters, editing)
cindex(editing parameters)
xitem(tt(vared) [ tt(-Aache) ] [ tt(-p) var(prompt) ] [ tt(-r) var(rprompt) ])
item(  [ -M var(main-keymap) ] [ -m var(vicmd-keymap) ] var(name))(
The value of the parameter var(name) is loaded into the edit
buffer, and the line editor is invoked.  When the editor exits,
var(name) is set to the string value returned by the editor.
When the tt(-c) flag is given, the parameter is created if it doesn't
already exist.  The tt(-a) flag may be given with tt(-c) to create
an array parameter, or the tt(-A) flag to create an associative array.
If the type of an existing parameter does not match the type to be
created, the parameter is unset and recreated.

If an array or array slice is being edited, separator characters as defined
in tt($IFS) will be shown quoted with a backslash, as will backslashes
themselves.  Conversely, when the edited text is split into an array, a
backslash quotes an immediately following separator character or backslash;
no other special handling of backslashes, or any handling of quotes, is
performed.

Individual elements of existing array or associative array parameters
may be edited by using subscript syntax on var(name).  New elements are
created automatically, even without tt(-c).

If the tt(-p) flag is given, the following string will be taken as
the prompt to display at the left.  If the tt(-r) flag is given,
the following string gives the prompt to display at the right.  If the
tt(-h) flag is specified, the history can be accessed from ZLE. If the
tt(-e) flag is given, typing tt(^D) (Control-D) on an empty line
causes tt(vared) to exit immediately with a non-zero return value.

The tt(-M) option gives a keymap to link to the tt(main) keymap during
editing, and the tt(-m) option gives a keymap to link to the tt(vicmd)
keymap during editing.  For vi-style editing, this allows a pair of keymaps
to override tt(viins) and tt(vicmd).  For emacs-style editing, only tt(-M)
is normally needed but the tt(-m) option may still be used.  On exit, the
previous keymaps will be restored.
)
findex(zle)
cindex(widgets, rebinding)
cindex(rebinding widgets)
cindex(widgets, binding)
cindex(binding widgets)
cindex(widgets, invoking)
cindex(invoking widgets)
cindex(widgets, calling)
cindex(calling widgets)
cindex(widgets, defining)
cindex(defining widgets)
xitem(tt(zle))
xitem(tt(zle) tt(-l) [ tt(-L) | tt(-a) ] [ var(string) ... ])
xitem(tt(zle) tt(-D) var(widget) ...)
xitem(tt(zle) tt(-A) var(old-widget) var(new-widget))
xitem(tt(zle) tt(-N) var(widget) [ var(function) ])
xitem(tt(zle) tt(-C) var(widget) var(completion-widget) var(function))
xitem(tt(zle) tt(-R) [ tt(-c) ] [ var(display-string) ] [ var(string) ... ])
xitem(tt(zle) tt(-M) var(string))
xitem(tt(zle) tt(-U) var(string))
xitem(tt(zle) tt(-K) var(keymap))
xitem(tt(zle) tt(-F) [ tt(-L) ] [ var(fd) [ var(handler) ] ])
xitem(tt(zle) tt(-I))
item(tt(zle) var(widget) tt([ -n) var(num) tt(]) tt([ -Nw ] [ -K) var(keymap) tt(]) var(args) ...)(
The tt(zle) builtin performs a number of different actions concerning
ZLE.

With no options and no arguments, only the return status will be
set.  It is zero if ZLE is currently active and widgets could be
invoked using this builtin command and non-zero otherwise.
Note that even if non-zero status is returned, zle may still be active as
part of the completion system; this does not allow direct calls to ZLE
widgets.

Otherwise, which operation it performs depends on its options:

startitem()
item(tt(-l) [ tt(-L) | tt(-a) ])(
List all existing user-defined widgets.  If the tt(-L)
option is used, list in the form of tt(zle)
commands to create the widgets.

When combined with the tt(-a) option, all widget names are listed,
including the builtin ones. In this case the tt(-L) option is ignored.

If at least one var(string) is given, nothing will be printed but the
return status will be zero if all var(string)s are names of existing
widgets (or of user-defined widgets if the tt(-a) flag is not given)
and non-zero if at least one var(string) is not a name of an defined
widget.
)
item(tt(-D) var(widget) ...)(
Delete the named var(widget)s.
)
item(tt(-A) var(old-widget) var(new-widget))(
Make the var(new-widget) name an alias for var(old-widget), so that
both names refer to the same widget.  The names have equal standing;
if either is deleted, the other remains.  If there is already a widget
with the var(new-widget) name, it is deleted.
)
item(tt(-N) var(widget) [ var(function) ])(
Create a user-defined widget.  If there is already a widget with the
specified name, it is overwritten.  When the new
widget is invoked from within the editor, the specified shell var(function)
is called.  If no function name is specified, it defaults to
the same name as the widget.  For further information, see the section
em(Widgets) in
ifzman(zmanref(zshzle))\
ifnzman(noderef(Zsh Line Editor))\
.
)
cindex(completion widgets, creating)
item(tt(-C) var(widget) var(completion-widget) var(function))(
Create a user-defined completion widget named var(widget). The 
completion widget will behave like the built-in completion-widget
whose name is given as var(completion-widget). To generate the
completions, the shell function var(function) will be called.
For further information, see
ifzman(zmanref(zshcompwid))\
ifnzman(noderef(Completion Widgets))\
.
)
item(tt(-R) [ tt(-c) ] [ var(display-string) ] [ var(string) ... ])(
Redisplay the command line; this is to be called from within a user-defined
widget to allow changes to become visible.  If a var(display-string) is
given and not empty, this is shown in the status line (immediately
below the line being edited).

If the optional var(string)s are given they are listed below the
prompt in the same way as completion lists are printed. If no
var(string)s are given but the tt(-c) option is used such a list is
cleared.

Note that this option is only useful for widgets that do not exit
immediately after using it because the strings displayed will be erased 
immediately after return from the widget.

This command can safely be called outside user defined widgets; if zle is
active, the display will be refreshed, while if zle is not active, the
command has no effect.  In this case there will usually be no other
arguments.

The status is zero if zle was active, else one.
)
item(tt(-M) var(string))(
As with the tt(-R) option, the var(string) will be displayed below the 
command line; unlike the tt(-R) option, the string will not be put into
the status line but will instead be printed normally below the
prompt.  This means that the var(string) will still be displayed after
the widget returns (until it is overwritten by subsequent commands).
)
item(tt(-U) var(string))(
This pushes the characters in the var(string) onto the input stack of
ZLE.  After the widget currently executed finishes ZLE will behave as
if the characters in the var(string) were typed by the user.

As ZLE uses a stack, if this option is used repeatedly
the last string pushed onto the stack will be processed first.  However,
the characters in each var(string) will be processed in the order in which
they appear in the string.
)
item(tt(-K) var(keymap))(
Selects the keymap named var(keymap).  An error message will be displayed if
there is no such keymap.

This keymap selection affects the interpretation of following keystrokes
within this invocation of ZLE.  Any following invocation (e.g., the next
command line) will start as usual with the `tt(main)' keymap selected.
)
item(tt(-F) [ tt(-L) ] [ var(fd) [ var(handler) ] ])(
Only available if your system supports one of the `poll' or `select' system
calls; most modern systems do.

Installs var(handler) (the name of a shell function) to handle input from
file descriptor var(fd).  When zle is attempting to read data, it will
examine both the terminal and the list of handled var(fd)'s.  If data
becomes available on a handled var(fd), zle will call var(handler) with
the fd which is ready for reading as the only argument.  If the handler
produces output to the terminal, it should call `tt(zle -I)' before doing
so (see below).  The handler should not attempt to read from the terminal.
Note that zle makes no attempt to check whether this fd is actually
readable when installing the handler.  The user must make their own
arrangements for handling the file descriptor when zle is not active.

Any number of handlers for any number of readable file descriptors may be
installed.  Installing a handler for an var(fd) which is already handled
causes the existing handler to be replaced.

If no var(handler) is given, but an var(fd) is present, any handler for
that var(fd) is removed.  If there is none, an error message is printed
and status 1 is returned.

If no arguments are given, or the tt(-L) option is supplied, a list of
handlers is printed in a form which can be stored for later execution.

An var(fd) (but not a var(handler)) may optionally be given with the tt(-L)
option; in this case, the function will list the handler if any, else
silently return status 1.

Note that this feature should be used with care.  Activity on one of the
var(fd)'s which is not properly handled can cause the terminal to become
unusable.

Here is a simple example of using this feature.  A connection to a remote
TCP port is created using the ztcp command; see 
ifzman(the description of the tt(zsh/net/tcp) module in zmanref(zshmodules))\
ifnzman(noderef(The zsh/net/tcp Module)).  Then a handler is installed
which simply prints out any data which arrives on this connection.  Note
that `select' will indicate that the file descriptor needs handling
if the remote side has closed the connection; we handle that by testing
for a failed read.
example(if ztcp pwspc 2811; then
  tcpfd=$REPLY
  handler+LPAR()RPAR() {
    zle -I
    local line
    if ! read -r line <&$1; then
      # select marks this fd if we reach EOF,
      # so handle this specially.
      print "[Read on fd $1 failed, removing.]" >&2
      zle -F $1
      return 1
    fi
    print -r - $line
  }
  zle -F $tcpfd handler
fi)
)
item(tt(-I))(
Unusually, this option is most useful outside ordinary widget functions,
though it may be used within if normal output to the terminal is required.
It invalidates the current zle display in preparation for output; typically
this will be from a trap function.  It has no effect if zle is not
active.  When a trap exits, the shell checks to see if the display needs
restoring, hence the following will print output in such a way as not to
disturb the line being edited:

example(TRAPUSR1() {
    # Invalidate zle display
  [[ -o zle ]] && zle -I
    # Show output
  print Hello
})

In general, the trap function may need to test whether zle is active before
using this method (as shown in the example), since the tt(zsh/zle) module
may not even be loaded; if it is not, the command can be skipped.

It is possible to call `tt(zle -I)' several times before control is
returned to the editor; the display will only be invalidated the first time
to minimise disruption.

Note that there are normally better ways of manipulating the display from
within zle widgets; see, for example, `tt(zle -R)' above.

The returned status is zero if zle was invalidated, even though
this may have been by a previous call to `tt(zle -I)' or by a system
notification.  To test if a zle widget may be called at this point, execute
tt(zle) with no arguments and examine the return status.
)
item(var(widget) tt([ -n) var(num) tt(]) tt([ -Nw ] [ -K) var(keymap) tt(]) var(args) ...)(
Invoke the specified widget.  This can only be done when ZLE is
active; normally this will be within a user-defined widget.

With the options tt(-n) and tt(-N), the current numerical argument will be
saved and then restored after the call to tt(widget); `tt(-n) var(num)'
sets the numerical argument temporarily to var(num), while `tt(-N)' sets it
to the default, i.e. as if there were none.

With the option tt(-K), var(keymap) will be used as the current keymap
during the execution of the widget.  The previous keymap will be
restored when the widget exits.

Normally, calling a widget in this way does not set the special
parameter tt(WIDGET) and related parameters, so that the environment
appears as if the top-level widget called by the user were still
active.  With the option tt(-w), tt(WIDGET) and related parameters are set
to reflect the widget being executed by the tt(zle) call.

Any further arguments will be passed to the widget; note that as
standard argument handling is performed, any general argument list
should be preceded by tt(-)tt(-).  If it is a shell
function, these are passed down as positional parameters; for builtin
widgets it is up to the widget in question what it does with them.
Currently arguments are only handled by the incremental-search commands,
the tt(history-search-forward) and tt(-backward) and the corresponding
functions prefixed by tt(vi-), and by tt(universal-argument).  No error is
flagged if the command does not use the arguments, or only uses some of
them.

The return status reflects the success or failure of the operation carried
out by the widget, or if it is a user-defined widget the return status of
the shell function.

A non-zero return status causes the shell to beep when the widget exits,
unless the tt(BEEP) options was unset or the widget was called via the
tt(zle) command.  Thus if a user defined widget requires an immediate beep,
it should call the tt(beep) widget directly.
)
enditem()
)
enditem()

texinode(Zle Widgets)(Character Highlighting)(Zle Builtins)(Zsh Line Editor)
sect(Widgets)
cindex(widgets)
All actions in the editor are performed by `widgets'.  A widget's job is
simply to perform some small action.  The ZLE commands that key sequences
in keymaps are bound to are in fact widgets.  Widgets can be user-defined
or built in.

The standard widgets built in to ZLE are listed in Standard Widgets below.
Other built-in widgets can be defined by other modules (see
ifzman(zmanref(zshmodules))\
ifnzman(noderef(Zsh Modules))\
).  Each built-in widget has two names: its normal canonical name, and the
same name preceded by a `tt(.)'.  The `tt(.)' name is special: it can't be
rebound to a different widget.  This makes the widget available even when
its usual name has been redefined.

User-defined widgets are defined using `tt(zle -N)', and implemented
as shell functions.  When the widget is executed, the corresponding
shell function is executed, and can perform editing (or other) actions.
It is recommended that user-defined widgets should not have names
starting with `tt(.)'.
sect(User-Defined Widgets)
cindex(widgets, user-defined)
User-defined widgets, being implemented as shell functions,
can execute any normal shell command.  They can also run other widgets
(whether built-in or user-defined) using the tt(zle) builtin command.
The standard input of the function is closed to prevent external commands
from unintentionally blocking ZLE by reading from the terminal, but
tt(read -k) or tt(read -q) can be used to read characters.  Finally,
they can examine and edit the ZLE buffer being edited by
reading and setting the special parameters described below.

cindex(parameters, editor)
cindex(parameters, zle)
These special parameters are always available in widget functions, but
are not in any way special outside ZLE.  If they have some normal value
outside ZLE, that value is temporarily inaccessible, but will return
when the widget function exits.  These special parameters in fact have
local scope, like parameters created in a function using tt(local).

Inside completion widgets and traps called while ZLE is active, these
parameters are available read-only.

startitem()
vindex(BUFFER)
item(tt(BUFFER) (scalar))(
The entire contents of the edit buffer.  If it is written to, the
cursor remains at the same offset, unless that would put it outside the
buffer.
)
vindex(BUFFERLINES)
item(tt(BUFFERLINES) (integer))(
The number of screen lines needed for the edit buffer currently
displayed on screen (i.e. without any changes to the preceding
parameters done after the last redisplay); read-only.
)
vindex(CONTEXT)
item(tt(CONTEXT) (scalar))(
The context in which zle was called to read a line; read-only.  One of
the values:
startitem()
item(start)(
The start of a command line (at prompt tt(PS1)).
)
item(cont)(
A continuation to a command line (at prompt tt(PS2)).
)
item(select)(
In a tt(select) loop.
)
item(vared)(
Editing a variable in tt(vared).
)
enditem()
)
vindex(CURSOR)
item(tt(CURSOR) (integer))(
The offset of the cursor, within the edit buffer.  This is in the range
0 to tt($#BUFFER), and is by definition equal to tt($#LBUFFER).
Attempts to move the cursor outside the buffer will result in the
cursor being moved to the appropriate end of the buffer.
)
vindex(CUTBUFFER)
item(tt(CUTBUFFER) (scalar))(
The last item to be cut using one of the `tt(kill-)' commands; the
string which the next yank would insert in the line.  Later entries in
the kill ring are in the array tt(killring).  Note that the
command `tt(zle copy-region-as-kill) var(string)' can be used to
set the text of the cut buffer from a shell function and cycle the kill
ring in the same way as interactively killing text.
)
vindex(HISTNO)
item(tt(HISTNO) (integer))(
The current history number.  Setting this has the same effect as
moving up or down in the history to the corresponding history line.
An attempt to set it is ignored if the line is not stored in the
history.  Note this is not the same as the parameter tt(HISTCMD),
which always gives the number of the history line being added to the main
shell's history.  tt(HISTNO) refers to the line being retrieved within
zle.
)
vindex(KEYMAP)
item(tt(KEYMAP) (scalar))(
The name of the currently selected keymap; read-only.
)
vindex(KEYS)
item(tt(KEYS) (scalar))(
The keys typed to invoke this widget, as a literal string; read-only.
)
vindex(killring)
item(tt(killring) (array))(
The array of previously killed items, with the most recently killed first.
This gives the items that would be retrieved by a tt(yank-pop) in the
same order.  Note, however, that the most recently killed item is in
tt($CUTBUFFER); tt($killring) shows the array of previous entries.

The default size for the kill ring is eight, however the length may be
changed by normal array operations.  Any empty string in the kill ring is
ignored by the tt(yank-pop) command, hence the size of the array
effectively sets the maximum length of the kill ring, while the number of
non-zero strings gives the current length, both as seen by the user at the
command line.
)

vindex(LASTSEARCH)
item(tt(LASTSEARCH) (scalar))(
The last search string used by an interactive search ; read-only.
)
vindex(LASTWIDGET)
item(tt(LASTWIDGET) (scalar))(
The name of the last widget that was executed; read-only.
)
vindex(LBUFFER)
item(tt(LBUFFER) (scalar))(
The part of the buffer that lies to the left of the cursor position.
If it is assigned to, only that part of the buffer is replaced, and the
cursor remains between the new tt($LBUFFER) and the old tt($RBUFFER).
)
vindex(MARK)
item(tt(MARK) (integer))(
Like tt(CURSOR), but for the mark.
)
vindex(NUMERIC)
item(tt(NUMERIC) (integer))(
The numeric argument. If no numeric argument was given, this parameter
is unset. When this is set inside a widget function, builtin widgets
called with the tt(zle) builtin command will use the value
assigned. If it is unset inside a widget function, builtin widgets
called behave as if no numeric argument was given.
)
vindex(PENDING)
item(tt(PENDING) (integer))(
The number of bytes pending for input, i.e. the number of bytes which have
already been typed and can immediately be read. On systems where the shell
is not able to get this information, this parameter will always have a
value of zero.  Read-only.
)
vindex(PREBUFFER)
item(tt(PREBUFFER) (scalar))(
In a multi-line input at the secondary prompt, this read-only parameter
contains the contents of the lines before the one the cursor is
currently in.
)
vindex(PREDISPLAY)
item(tt(PREDISPLAY) (scalar))(
Text to be displayed before the start of the editable text buffer.  This
does not have to be a complete line; to display a complete line, a newline
must be appended explicitly.    The text is reset on each new invocation
(but not recursive invocation) of zle.
)
vindex(POSTDISPLAY)
item(tt(POSTDISPLAY) (scalar))(
Text to be displayed after the end of the editable text buffer.  This
does not have to be a complete line; to display a complete line, a newline
must be prepended explicitly.  The text is reset on each new invocation
(but not recursive invocation) of zle.
)
vindex(RBUFFER)
item(tt(RBUFFER) (scalar))(
The part of the buffer that lies to the right of the cursor position.
If it is assigned to, only that part of the buffer is replaced, and the
cursor remains between the old tt($LBUFFER) and the new tt($RBUFFER).
)
vindex(REGION_ACTIVE)
item(tt(REGION_ACTIVE) (integer))(
Indicates if the region is currently active.  It can be assigned 0 or 1
to deactivate and activate the region respectively;
ifzman(see em(Character Highlighting) below)\
ifnzman(noderef(Character Highlighting)).
)
vindex(region_highlight)
item(tt(region_highlight) (array))(
Each element of this array may be set to a string that describes
highlighting for an arbitrary region of the command line that will
take effect the next time the command line is redisplayed.  Highlighting
of the non-editable parts of the command line in tt(PREDISPLAY)
and tt(POSTDISPLAY) are possible, but note that the tt(P) flag
is needed for character indexing to include tt(PREDISPLAY).

Each string consists of the following parts:

startlist()
list(Optionally, a `tt(P)' to signify that the start and end offset that
follow include any string set by the tt(PREDISPLAY) special parameter;
this is needed if the predisplay string itself is to be highlighted.
Whitespace may follow the `tt(P)'.)
list(A start offset in the same units as tt(CURSOR), terminated by
whitespace.)
list(An end offset in the same units as tt(CURSOR), terminated by
whitespace.)
list(A highlight specification in the same format as
used for the contexts tt(region) or tt(special)
in the parameter tt(zle_highlight),
ifnzman(noderef(Character Highlighting))\
ifzman(see Character Highlighting below).
Hence this should be a comma-separated list of any of the
words tt(bold), tt(standout) or tt(underline).
endlist()

For example, 

example(region_highlight=("P0 20 bold"))

specifies that the first twenty characters of the text including
any predisplay string should be highlighted in bold.

Note that the effect of tt(region_highlight) is not saved and disappears
as soon as the line is accepted.  The line editor makes no attempt to
keep the highlighting effect synchronised with the line as it is edited;
hence region highlighting is best limited to static effects within
user widgets.
)
)
vindex(WIDGET)
item(tt(WIDGET) (scalar))(
The name of the widget currently being executed; read-only.
)
vindex(WIDGETFUNC)
item(tt(WIDGETFUNC) (scalar))(
The name of the shell function that implements a widget defined with
either tt(zle -N) or tt(zle -C).  In the former case, this is the second
argument to the tt(zle -N) command that defined the widget, or
the first argument if there was no second argument.  In the latter case
this is the the third argument to the tt(zle -C) command that defined the
widget.  Read-only.
)
vindex(WIDGETSTYLE)
item(tt(WIDGETSTYLE) (scalar))(
Describes the implementation behind the completion widget currently being
executed; the second argument that followed tt(zle -C) when the widget was
defined.  This is the name of a builtin completion widget.  For widgets
defined with tt(zle -N) this is set to the empty string.  Read-only.
)
enditem()

subsect(Special Widgets)

There are a few user-defined widgets which are special to the shell.
If they do not exist, no special action is taken.  The environment
provided is identical to that for any other editing widget.

startitem()
tindex(zle-line-init)
item(tt(zle-line-init))(
Executed every time the line editor is started to read a new line
of input.  The following example puts the line editor into vi command
mode when it starts up.

example(zle-line-init+LPAR()RPAR() { zle -K vicmd; }
zle -N zle-line-init)

(The command inside the function sets the keymap directly; it is
equivalent to tt(zle vi-cmd-mode).)
)
tindex(zle-keymap-select)
item(tt(zle-keymap-select))(
Executed every time the keymap changes, i.e. the special parameter
tt(KEYMAP) is set to a different value, while the line editor is active.
Initialising the keymap when the line editor starts does not cause the
widget to be called.

The value tt($KEYMAP) within the function reflects the new keymap.  The
old keymap is passed as the sole argument.

This can been used for detecting switches between the vi command
(tt(vicmd)) and insert (usually tt(main)) keymaps.
)
enditem()

sect(Standard Widgets)
cindex(widgets, standard)
The following is a list of all the standard widgets,
and their default bindings in emacs mode,
vi command mode and vi insert mode
(the `tt(emacs)', `tt(vicmd)' and `tt(viins)' keymaps, respectively).

Note that cursor keys are bound to movement keys in all three keymaps;
the shell assumes that the cursor keys send the key sequences reported
by the terminal-handling library (termcap or terminfo).  The key sequences
shown in the list are those based on the VT100, common on many modern
terminals, but in fact these are not necessarily bound.  In the case of the
tt(viins) keymap, the initial escape character of the sequences serves also
to return to the tt(vicmd) keymap: whether this happens is determined by
the tt(KEYTIMEOUT) parameter, see ifzman(zmanref(zshparam))\
ifnzman(noderef(Parameters)).
startmenu()
menu(Movement)
menu(History Control)
menu(Modifying Text)
menu(Arguments)
menu(Completion)
menu(Miscellaneous)
endmenu()
texinode(Movement)(History Control)()(Zle Widgets)
subsect(Movement)
startitem()
tindex(vi-backward-blank-word)
item(tt(vi-backward-blank-word) (unbound) (B) (unbound))(
Move backward one word, where a word is defined as a series of
non-blank characters.
)
tindex(backward-char)
item(tt(backward-char) (^B ESC-[D) (unbound) (unbound))(
Move backward one character.
)
tindex(vi-backward-char)
item(tt(vi-backward-char) (unbound) (^H h ^?) (ESC-[D))(
Move backward one character, without changing lines.
)
tindex(backward-word)
item(tt(backward-word) (ESC-B ESC-b) (unbound) (unbound))(
Move to the beginning of the previous word.
)
tindex(emacs-backward-word)
item(tt(emacs-backward-word))(
Move to the beginning of the previous word.
)
tindex(vi-backward-word)
item(tt(vi-backward-word) (unbound) (b) (unbound))(
Move to the beginning of the previous word, vi-style.
)
tindex(beginning-of-line)
item(tt(beginning-of-line) (^A) (unbound) (unbound))(
Move to the beginning of the line.  If already at the beginning
of the line, move to the beginning of the previous line, if any.
)
tindex(vi-beginning-of-line)
item(tt(vi-beginning-of-line))(
Move to the beginning of the line, without changing lines.
)
tindex(end-of-line)
item(tt(end-of-line) (^E) (unbound) (unbound))(
Move to the end of the line.  If already at the end
of the line, move to the end of the next line, if any.
)
tindex(vi-end-of-line)
item(tt(vi-end-of-line) (unbound) ($) (unbound))(
Move to the end of the line.
If an argument is given to this command, the cursor will be moved to
the end of the line (argument - 1) lines down.
)
tindex(vi-forward-blank-word)
item(tt(vi-forward-blank-word) (unbound) (W) (unbound))(
Move forward one word, where a word is defined as a series of
non-blank characters.
)
tindex(vi-forward-blank-word-end)
item(tt(vi-forward-blank-word-end) (unbound) (E) (unbound))(
Move to the end of the current word, or, if at the end of the current word,
to the end of the next word,
where a word is defined as a series of non-blank characters.
)
tindex(forward-char)
item(tt(forward-char) (^F ESC-[C) (unbound) (unbound))(
Move forward one character.
)
tindex(vi-forward-char)
item(tt(vi-forward-char) (unbound) (space l) (ESC-[C))(
Move forward one character.
)
tindex(vi-find-next-char)
item(tt(vi-find-next-char) (^X^F) (f) (unbound))(
Read a character from the keyboard, and move to
the next occurrence of it in the line.
)
tindex(vi-find-next-char-skip)
item(tt(vi-find-next-char-skip) (unbound) (t) (unbound))(
Read a character from the keyboard, and move to
the position just before the next occurrence of it in the line.
)
tindex(vi-find-prev-char)
item(tt(vi-find-prev-char) (unbound) (F) (unbound))(
Read a character from the keyboard, and move to
the previous occurrence of it in the line.
)
tindex(vi-find-prev-char-skip)
item(tt(vi-find-prev-char-skip) (unbound) (T) (unbound))(
Read a character from the keyboard, and move to
the position just after the previous occurrence of it in the line.
)
tindex(vi-first-non-blank)
item(tt(vi-first-non-blank) (unbound) (^) (unbound))(
Move to the first non-blank character in the line.
)
tindex(vi-forward-word)
item(tt(vi-forward-word) (unbound) (w) (unbound))(
Move forward one word, vi-style.
)
tindex(forward-word)
item(tt(forward-word) (ESC-F ESC-f) (unbound) (unbound))(
Move to the beginning of the next word.
The editor's idea of a word is specified with the tt(WORDCHARS)
parameter.
)
tindex(emacs-forward-word)
item(tt(emacs-forward-word))(
Move to the end of the next word.
)
tindex(vi-forward-word-end)
item(tt(vi-forward-word-end) (unbound) (e) (unbound))(
Move to the end of the next word.
)
tindex(vi-goto-column)
item(tt(vi-goto-column) (ESC-|) (|) (unbound))(
Move to the column specified by the numeric argument.
)
tindex(vi-goto-mark)
item(tt(vi-goto-mark) (unbound) (`) (unbound))(
Move to the specified mark.
)
tindex(vi-goto-mark-line)
item(tt(vi-goto-mark-line) (unbound) (') (unbound))(
Move to beginning of the line containing the specified mark.
)
tindex(vi-repeat-find)
item(tt(vi-repeat-find) (unbound) (;) (unbound))(
Repeat the last tt(vi-find) command.
)
tindex(vi-rev-repeat-find)
item(tt(vi-rev-repeat-find) (unbound) (,) (unbound))(
Repeat the last tt(vi-find) command in the opposite direction.
)
enditem()
texinode(History Control)(Modifying Text)(Movement)(Zle Widgets)
subsect(History Control)
startitem()
tindex(beginning-of-buffer-or-history)
item(tt(beginning-of-buffer-or-history) (ESC-<) (unbound) (unbound))(
Move to the beginning of the buffer, or if already there,
move to the first event in the history list.
)
tindex(beginning-of-line-hist)
item(tt(beginning-of-line-hist))(
Move to the beginning of the line.  If already at the
beginning of the buffer, move to the previous history line.
)
tindex(beginning-of-history)
item(tt(beginning-of-history))(
Move to the first event in the history list.
)
tindex(down-line-or-history)
item(tt(down-line-or-history) (^N ESC-[B) (j) (ESC-[B))(
Move down a line in the buffer, or if already at the bottom line,
move to the next event in the history list.
)
tindex(vi-down-line-or-history)
item(tt(vi-down-line-or-history) (unbound) (PLUS()) (unbound))(
Move down a line in the buffer, or if already at the bottom line,
move to the next event in the history list.
Then move to the first non-blank character on the line.
)
tindex(down-line-or-search)
item(tt(down-line-or-search))(
Move down a line in the buffer, or if already at the bottom line,
search forward in the history for a line beginning with the first
word in the buffer.

If called from a function by the tt(zle) command with arguments, the first
argument is taken as the string for which to search, rather than the
first word in the buffer.
)
tindex(down-history)
item(tt(down-history) (unbound) (^N) (unbound))(
Move to the next event in the history list.
)
tindex(history-beginning-search-backward)
item(tt(history-beginning-search-backward))(
Search backward in the history for a line beginning with the current
line up to the cursor.
This leaves the cursor in its original position.
)
tindex(end-of-buffer-or-history)
item(tt(end-of-buffer-or-history) (ESC->) (unbound) (unbound))(
Move to the end of the buffer, or if already there,
move to the last event in the history list.
)
tindex(end-of-line-hist)
item(tt(end-of-line-hist))(
Move to the end of the line.  If already at the end of
the buffer, move to the next history line.
)
tindex(end-of-history)
item(tt(end-of-history))(
Move to the last event in the history list.
)
tindex(vi-fetch-history)
item(tt(vi-fetch-history) (unbound) (G) (unbound))(
Fetch the history line specified by the numeric argument.
This defaults to the current history line
(i.e. the one that isn't history yet).
)
tindex(history-incremental-search-backward)
item(tt(history-incremental-search-backward) (^R ^Xr) (unbound) (unbound))(
Search backward incrementally for a specified string.  The search is
case-insensitive if the search string does not have uppercase letters and no
numeric argument was given.  The string may begin with `tt(^)' to anchor the
search to the beginning of the line.

A restricted set of editing functions
is available in the mini-buffer.  An interrupt signal, as defined by the stty
setting, will stop the search and go back to the original line.  An undefined
key will have the same effect. The supported functions are:

startitem()
xitem(tt(accept-and-hold))
xitem(tt(accept-and-infer-next-history))
xitem(tt(accept-line))
item(tt(accept-line-and-down-history))(
Perform the usual function after exiting incremental search.
The command line displayed is executed.
)
xitem(tt(backward-delete-char))
item(tt(vi-backward-delete-char))(
Back up one place in the search history.  If the search has been
repeated this does not immediately erase a character in the
minibuffer.
)
xitem(tt(backward-delete-word))
xitem(tt(backward-kill-word))
item(tt(vi-backward-kill-word))(
Back up one character in the minibuffer; if multiple searches
have been performed since the character was inserted the search
history is rewound to the point just before the character was
entered.  Hence this has the effect of repeating
tt(backward-delete-char).
)
item(tt(clear-screen))(
Clear the screen, remaining in incremental search mode.
)
item(tt(history-incremental-search-backward))(
Find the next occurrence of the contents of the mini-buffer.
)
item(tt(history-incremental-search-forward))(
Invert the sense of the search.
)
item(tt(magic-space))(
Inserts a non-magical space.
)
xitem(tt(quoted-insert))
item(tt(vi-quoted-insert))(
Quote the character to insert into the minibuffer.
)
item(tt(redisplay))(
Redisplay the command line, remaining in incremental search mode.
)
item(tt(vi-cmd-mode))(
Toggle between the `tt(main)' and `tt(vicmd)' keymaps;
the `tt(main)' keymap (insert mode) will be selected initially.
)
xitem(tt(vi-repeat-search))
item(tt(vi-rev-repeat-search))(
Repeat the search.  The direction of the search is indicated in the
mini-buffer.
)
enditem()

Any multi-character string that is not bound to one of the above functions
will beep and interrupt the search, leaving the last found line in the
buffer. Any single character that is not bound to one of the above
functions, or tt(self-insert) or tt(self-insert-unmeta), will have the same
effect but the function will be executed.

When called from a widget function by the tt(zle) command, the incremental
search commands can take a string argument.  This will be treated as a
string of keys, as for arguments to the tt(bindkey) command, and used as
initial input for the command.  Any characters in the string which are
unused by the incremental search will be silently ignored.  For example,

example(zle history-incremental-search-backward forceps)

will search backwards for tt(forceps), leaving the minibuffer containing
the string `tt(forceps)'.
)
tindex(history-incremental-search-forward)
item(tt(history-incremental-search-forward) (^S ^Xs) (unbound) (unbound))(
Search forward incrementally for a specified string.  The search is
case-insensitive if the search string does not have uppercase letters and no
numeric argument was given.  The string may begin with `tt(^)' to anchor the
search to the beginning of the line.  The functions available in the
mini-buffer are the same as for tt(history-incremental-search-backward).
)
tindex(history-incremental-pattern-search-backward)
tindex(history-incremental-pattern-search-forward)
xitem(tt(history-incremental-pattern-search-backward))
item(tt(history-incremental-pattern-search-forward))(
These widgets behave similarly to the corresponding widgets with
no tt(-pattern), but the search string typed by the user is treated
as a pattern, respecting the current settings of the various options
affecting pattern matching.  See
ifzman(FILENAME GENERATION in zmanref(zshexpn))\
ifnzman(noderef(Filename Generation)) for a description of patterns.
If no numeric argument was given lowercase letters in the search
string may match uppercase letters in the history.  The string may begin
with `tt(^)' to anchor the search to the beginning of the line.

The prompt changes to indicate an invalid pattern; this may simply
indicate the pattern is not yet complete.

Note that only non-overlapping matches are reported, so an expression
with wildcards may return fewer matches on a line than are visible
by inspection.
)
tindex(history-search-backward)
item(tt(history-search-backward) (ESC-P ESC-p) (unbound) (unbound))(
Search backward in the history for a line beginning with the first
word in the buffer.

If called from a function by the tt(zle) command with arguments, the first
argument is taken as the string for which to search, rather than the
first word in the buffer.
)
tindex(vi-history-search-backward)
item(tt(vi-history-search-backward) (unbound) (/) (unbound))(
Search backward in the history for a specified string.
The string may begin with `tt(^)' to anchor the search to the
beginning of the line.

A restricted set of editing functions is available in
the mini-buffer.  An interrupt signal, as defined by the stty setting,  will
stop the search.
The functions available in the mini-buffer are:
tt(accept-line),
tt(backward-delete-char),
tt(vi-backward-delete-char),
tt(backward-kill-word),
tt(vi-backward-kill-word),
tt(clear-screen),
tt(redisplay),
tt(quoted-insert)
and
tt(vi-quoted-insert).

tt(vi-cmd-mode) is treated the same as accept-line, and
tt(magic-space) is treated as a space.
Any other character that is not bound to self-insert or
self-insert-unmeta will beep and be ignored. If the function is called from vi
command mode, the bindings of the current insert mode will be used.

If called from a function by the tt(zle) command with arguments, the first
argument is taken as the string for which to search, rather than the
first word in the buffer.
)
tindex(history-search-forward)
item(tt(history-search-forward) (ESC-N ESC-n) (unbound) (unbound))(
Search forward in the history for a line beginning with the first
word in the buffer.

If called from a function by the tt(zle) command with arguments, the first
argument is taken as the string for which to search, rather than the
first word in the buffer.
)
tindex(vi-history-search-forward)
item(tt(vi-history-search-forward) (unbound) (?) (unbound))(
Search forward in the history for a specified string.
The string may begin with `tt(^)' to anchor the search to the
beginning of the line. The functions available in the mini-buffer are the same
as for tt(vi-history-search-backward).  Argument handling is also the same
as for that command.
)
tindex(infer-next-history)
item(tt(infer-next-history) (^X^N) (unbound) (unbound))(
Search in the history list for a line matching the current one and
fetch the event following it.
)
tindex(insert-last-word)
item(tt(insert-last-word) (ESC-_ ESC-.) (unbound) (unbound))(
Insert the last word from the previous history event at the
cursor position.  If a positive numeric argument is given,
insert that word from the end of the previous history event.
If the argument is zero or negative insert that word from the
left (zero inserts the previous command word).  Repeating this command
replaces the word just inserted with the last word from the
history event prior to the one just used; numeric arguments can be used in
the same way to pick a word from that event.

When called from a shell function invoked from a user-defined widget, the
command can take one to three arguments.  The first argument specifies a
history offset which applies to successive calls to this widget: if is -1,
the default behaviour is used, while if it is 1, successive calls will move
forwards through the history.  The value 0 can be used to indicate that the
history line examined by the previous execution of the command will be
reexamined.  Note that negative numbers should be preceded with a
`tt(-)tt(-)' argument to avoid confusing them with options.

If two arguments are given, the second specifies the word on the command
line in normal array index notation (as a more natural alternative to the
prefix argument).  Hence 1 is the first word, and -1 (the default) is the
last word.

If a third argument is given, its value is ignored, but it is used to
signify that the history offset is relative to the current history line,
rather than the one remembered after the previous invocations of
tt(insert-last-word).

For example, the default behaviour of the command corresponds to

example(zle insert-last-word -- -1 -1)

while the command

example(zle insert-last-word -- -1 1 -)

always copies the first word of the line in the history immediately before
the line being edited.  This has the side effect that later invocations of
the widget will be relative to that line.
)
tindex(vi-repeat-search)
item(tt(vi-repeat-search) (unbound) (n) (unbound))(
Repeat the last vi history search.
)
tindex(vi-rev-repeat-search)
item(tt(vi-rev-repeat-search) (unbound) (N) (unbound))(
Repeat the last vi history search, but in reverse.
)
tindex(up-line-or-history)
item(tt(up-line-or-history) (^P ESC-[A) (k) (ESC-[A))(
Move up a line in the buffer, or if already at the top line,
move to the previous event in the history list.
)
tindex(vi-up-line-or-history)
item(tt(vi-up-line-or-history) (unbound) (-) (unbound))(
Move up a line in the buffer, or if already at the top line,
move to the previous event in the history list.
Then move to the first non-blank character on the line.
)
tindex(up-line-or-search)
item(tt(up-line-or-search))(
Move up a line in the buffer, or if already at the top line,
search backward in the history for a line beginning with the
first word in the buffer.

If called from a function by the tt(zle) command with arguments, the first
argument is taken as the string for which to search, rather than the
first word in the buffer.
)
tindex(up-history)
item(tt(up-history) (unbound) (^P) (unbound))(
Move to the previous event in the history list.
)
tindex(history-beginning-search-forward)
item(tt(history-beginning-search-forward))(
Search forward in the history for a line beginning with the current
line up to the cursor.
This leaves the cursor in its original position.
)
enditem()
texinode(Modifying Text)(Arguments)(History Control)(Zle Widgets)
subsect(Modifying Text)
startitem()
tindex(vi-add-eol)
item(tt(vi-add-eol) (unbound) (A) (unbound))(
Move to the end of the line and enter insert mode.
)
tindex(vi-add-next)
item(tt(vi-add-next) (unbound) (a) (unbound))(
Enter insert mode after the current cursor position, without changing lines.
)
tindex(backward-delete-char)
item(tt(backward-delete-char) (^H ^?) (unbound) (unbound))(
Delete the character behind the cursor.
)
tindex(vi-backward-delete-char)
item(tt(vi-backward-delete-char) (unbound) (X) (^H))(
Delete the character behind the cursor, without changing lines.
If in insert mode, this won't delete past the point where insert mode was
last entered.
)
tindex(backward-delete-word)
item(tt(backward-delete-word))(
Delete the word behind the cursor.
)
tindex(backward-kill-line)
item(tt(backward-kill-line))(
Kill from the beginning of the line to the cursor position.
)
tindex(backward-kill-word)
item(tt(backward-kill-word) (^W ESC-^H ESC-^?) (unbound) (unbound))(
Kill the word behind the cursor.
)
tindex(vi-backward-kill-word)
item(tt(vi-backward-kill-word) (unbound) (unbound) (^W))(
Kill the word behind the cursor, without going past the point where insert
mode was last entered.
)
tindex(capitalize-word)
item(tt(capitalize-word) (ESC-C ESC-c) (unbound) (unbound))(
Capitalize the current word and move past it.
)
tindex(vi-change)
item(tt(vi-change) (unbound) (c) (unbound))(
Read a movement command from the keyboard, and kill
from the cursor position to the endpoint of the movement.
Then enter insert mode.
If the command is tt(vi-change), change the current line.
)
tindex(vi-change-eol)
item(tt(vi-change-eol) (unbound) (C) (unbound))(
Kill to the end of the line and enter insert mode.
)
tindex(vi-change-whole-line)
item(tt(vi-change-whole-line) (unbound) (S) (unbound))(
Kill the current line and enter insert mode.
)
tindex(copy-region-as-kill)
item(tt(copy-region-as-kill) (ESC-W ESC-w) (unbound) (unbound))(
Copy the area from the cursor to the mark to the kill buffer.

If called from a ZLE widget function in the form `tt(zle
copy-region-as-kill) var(string)' then var(string) will be taken as the
text to copy to the kill buffer.  The cursor, the mark and the text on the
command line are not used in this case.
)
tindex(copy-prev-word)
item(tt(copy-prev-word) (ESC-^_) (unbound) (unbound))(
Duplicate the word to the left of the cursor.
)
tindex(copy-prev-shell-word)
item(tt(copy-prev-shell-word))(
Like tt(copy-prev-word), but the word is found by using shell parsing, 
whereas tt(copy-prev-word) looks for blanks. This makes a difference
when the word is quoted and contains spaces.
)
tindex(vi-delete)
item(tt(vi-delete) (unbound) (d) (unbound))(
Read a movement command from the keyboard, and kill
from the cursor position to the endpoint of the movement.
If the command is tt(vi-delete), kill the current line.
)
tindex(delete-char)
item(tt(delete-char))(
Delete the character under the cursor.
)
tindex(vi-delete-char)
item(tt(vi-delete-char) (unbound) (x) (unbound))(
Delete the character under the cursor,
without going past the end of the line.
)
tindex(delete-word)
item(tt(delete-word))(
Delete the current word.
)
tindex(down-case-word)
item(tt(down-case-word) (ESC-L ESC-l) (unbound) (unbound))(
Convert the current word to all lowercase and move past it.
)
tindex(kill-word)
item(tt(kill-word) (ESC-D ESC-d) (unbound) (unbound))(
Kill the current word.
)
tindex(gosmacs-transpose-chars)
item(tt(gosmacs-transpose-chars))(
Exchange the two characters behind the cursor.
)
tindex(vi-indent)
item(tt(vi-indent) (unbound) (>) (unbound))(
Indent a number of lines.
)
tindex(vi-insert)
item(tt(vi-insert) (unbound) (i) (unbound))(
Enter insert mode.
)
tindex(vi-insert-bol)
item(tt(vi-insert-bol) (unbound) (I) (unbound))(
Move to the first non-blank character on the line and enter insert mode.
)
tindex(vi-join)
item(tt(vi-join) (^X^J) (J) (unbound))(
Join the current line with the next one.
)
tindex(kill-line)
item(tt(kill-line) (^K) (unbound) (unbound))(
Kill from the cursor to the end of the line.
If already on the end of the line, kill the newline character.
)
tindex(vi-kill-line)
item(tt(vi-kill-line) (unbound) (unbound) (^U))(
Kill from the cursor back to wherever insert mode was last entered.
)
tindex(vi-kill-eol)
item(tt(vi-kill-eol) (unbound) (D) (unbound))(
Kill from the cursor to the end of the line.
)
tindex(kill-region)
item(tt(kill-region))(
Kill from the cursor to the mark.
)
tindex(kill-buffer)
item(tt(kill-buffer) (^X^K) (unbound) (unbound))(
Kill the entire buffer.
)
tindex(kill-whole-line)
item(tt(kill-whole-line) (^U) (unbound) (unbound))(
Kill the current line.
)
tindex(vi-match-bracket)
item(tt(vi-match-bracket) (^X^B) (%) (unbound))(
Move to the bracket character (one of tt({}), tt(()) or tt([])) that
matches the one under the cursor.
If the cursor is not on a bracket character, move forward without going
past the end of the line to find one, and then go to the matching bracket.
)
tindex(vi-open-line-above)
item(tt(vi-open-line-above) (unbound) (O) (unbound))(
Open a line above the cursor and enter insert mode.
)
tindex(vi-open-line-below)
item(tt(vi-open-line-below) (unbound) (o) (unbound))(
Open a line below the cursor and enter insert mode.
)
tindex(vi-oper-swap-case)
item(tt(vi-oper-swap-case))(
Read a movement command from the keyboard, and swap
the case of all characters
from the cursor position to the endpoint of the movement.
If the movement command is tt(vi-oper-swap-case),
swap the case of all characters on the current line.
)
tindex(overwrite-mode)
item(tt(overwrite-mode) (^X^O) (unbound) (unbound))(
Toggle between overwrite mode and insert mode.
)
tindex(vi-put-before)
item(tt(vi-put-before) (unbound) (P) (unbound))(
Insert the contents of the kill buffer before the cursor.
If the kill buffer contains a sequence of lines (as opposed to characters),
paste it above the current line.
)
tindex(vi-put-after)
item(tt(vi-put-after) (unbound) (p) (unbound))(
Insert the contents of the kill buffer after the cursor.
If the kill buffer contains a sequence of lines (as opposed to characters),
paste it below the current line.
)
tindex(quoted-insert)
item(tt(quoted-insert) (^V) (unbound) (unbound))(
Insert the next character typed into the buffer literally.
An interrupt character will not be inserted.
)
tindex(vi-quoted-insert)
item(tt(vi-quoted-insert) (unbound) (unbound) (^Q ^V))(
Display a `tt(^)' at the cursor position, and
insert the next character typed into the buffer literally.
An interrupt character will not be inserted.
)
tindex(quote-line)
item(tt(quote-line) (ESC-') (unbound) (unbound))(
Quote the current line; that is, put a `tt(')' character at the
beginning and the end, and convert all `tt(')' characters
to `tt('\'')'.
)
tindex(quote-region)
item(tt(quote-region) (ESC-") (unbound) (unbound))(
Quote the region from the cursor to the mark.
)
tindex(vi-replace)
item(tt(vi-replace) (unbound) (R) (unbound))(
Enter overwrite mode.
)
tindex(vi-repeat-change)
item(tt(vi-repeat-change) (unbound) (.) (unbound))(
Repeat the last vi mode text modification.
If a count was used with the modification, it is remembered.
If a count is given to this command, it overrides the remembered count,
and is remembered for future uses of this command.
The cut buffer specification is similarly remembered.
)
tindex(vi-replace-chars)
item(tt(vi-replace-chars) (unbound) (r) (unbound))(
Replace the character under the cursor with a character
read from the keyboard.
)
tindex(self-insert)
item(tt(self-insert) (printable characters) (unbound) (printable characters and some control characters))(
Insert a character into the buffer at the cursor position.
)
tindex(self-insert-unmeta)
item(tt(self-insert-unmeta) (ESC-^I ESC-^J ESC-^M) (unbound) (unbound))(
Insert a character into the buffer after stripping the meta bit
and converting ^M to ^J.
)
tindex(vi-substitute)
item(tt(vi-substitute) (unbound) (s) (unbound))(
Substitute the next characte+CHAR(r)(s).
)
tindex(vi-swap-case)
item(tt(vi-swap-case) (unbound) (~) (unbound))(
Swap the case of the character under the cursor and move past it.
)
tindex(transpose-chars)
item(tt(transpose-chars) (^T) (unbound) (unbound))(
Exchange the two characters to the left of the
cursor if at end of line, else exchange the
character under the cursor with the character
to the left.
)
tindex(transpose-words)
item(tt(transpose-words) (ESC-T ESC-t) (unbound) (unbound))(
Exchange the current word with the one before it.
)
tindex(vi-unindent)
item(tt(vi-unindent) (unbound) (<) (unbound))(
Unindent a number of lines.
)
tindex(up-case-word)
item(tt(up-case-word) (ESC-U ESC-u) (unbound) (unbound))(
Convert the current word to all caps and move past it.
)
tindex(yank)
item(tt(yank) (^Y) (unbound) (unbound))(
Insert the contents of the kill buffer at the cursor position.
)
tindex(yank-pop)
item(tt(yank-pop) (ESC-y) (unbound) (unbound))(
Remove the text just yanked, rotate the kill-ring (the history of
previously killed text) and yank the new top.  Only works following
tt(yank) or tt(yank-pop).
)
tindex(vi-yank)
item(tt(vi-yank) (unbound) (y) (unbound))(
Read a movement command from the keyboard, and copy the region
from the cursor position to the endpoint of the movement
into the kill buffer.
If the command is tt(vi-yank), copy the current line.
)
tindex(vi-yank-whole-line)
item(tt(vi-yank-whole-line) (unbound) (Y) (unbound))(
Copy the current line into the kill buffer.
)
tindex(vi-yank-eol)
item(tt(vi-yank-eol))(
Copy the region from the cursor position to the end of the line
into the kill buffer.
Arguably, this is what Y should do in vi, but it isn't what it actually does.
)
enditem()
texinode(Arguments)(Completion)(Modifying Text)(Zle Widgets)
subsect(Arguments)
startitem()
tindex(digit-argument)
item(tt(digit-argument) (ESC-0..ESC-9) (1-9) (unbound))(
Start a new numeric argument, or add to the current one.
See also tt(vi-digit-or-beginning-of-line).  This only works if bound to a
key sequence ending in a decimal digit.

Inside a widget function, a call to this function treats the last key of
the key sequence which called the widget as the digit.
)
tindex(neg-argument)
item(tt(neg-argument) (ESC-DASH()) (unbound) (unbound))(
Changes the sign of the following argument.
)
tindex(universal-argument)
item(tt(universal-argument))(
Multiply the argument of the next command by 4.  Alternatively, if
this command is followed by an integer (positive or negative), use
that as the argument for the next command.  Thus digits cannot be
repeated using this command.  For example, if this command occurs
twice, followed immediately by tt(forward-char), move forward sixteen
spaces; if instead it is followed by tt(-2), then tt(forward-char),
move backward two spaces.

Inside a widget function, if passed an argument, i.e. `tt(zle
universal-argument) var(num)', the numerical argument will be set to
var(num); this is equivalent to `tt(NUMERIC=)var(num)'.
)
tindex(argument-base)
item(tt(argument-base))(
Use the existing numeric argument as a numeric base, which must be in the
range 2 to 36 inclusive.  Subsequent use of tt(digit-argument) and
tt(universal-argument) will input a new prefix in the given base.
The usual hexadecimal convention is used: the letter tt(a) or tt(A)
corresponds to 10, and so on.  Arguments in bases requiring digits from 10
upwards are more conveniently input with tt(universal-argument), since
tt(ESC-a) etc. are not usually bound to tt(digit-argument).

The function can be used with a command argument inside a user-defined
widget.  The following code sets the base to 16 and lets the user input a
hexadecimal argument until a key out of the digit range is typed:

example(zle argument-base 16
zle universal-argument)
)
enditem()
texinode(Completion)(Miscellaneous)(Arguments)(Zle Widgets)
subsect(Completion)
startitem()
tindex(accept-and-menu-complete)
item(tt(accept-and-menu-complete))(
In a menu completion, insert the current completion into the buffer,
and advance to the next possible completion.
)
tindex(complete-word)
item(tt(complete-word))(
Attempt completion on the current word.
)
tindex(delete-char-or-list)
item(tt(delete-char-or-list) (^D) (unbound) (unbound))(
Delete the character under the cursor.  If the cursor
is at the end of the line, list possible completions for the
current word.
)
tindex(expand-cmd-path)
item(tt(expand-cmd-path))(
Expand the current command to its full pathname.
)
tindex(expand-or-complete)
item(tt(expand-or-complete) (TAB) (unbound) (TAB))(
Attempt shell expansion on the current word.
If that fails,
attempt completion.
)
tindex(expand-or-complete-prefix)
item(tt(expand-or-complete-prefix))(
Attempt shell expansion on the current word up to cursor.
)
tindex(expand-history)
item(tt(expand-history) (ESC-space ESC-!) (unbound) (unbound))(
Perform history expansion on the edit buffer.
)
tindex(expand-word)
item(tt(expand-word) (^X*) (unbound) (unbound))(
Attempt shell expansion on the current word.
)
tindex(list-choices)
item(tt(list-choices) (ESC-^D) (^D =) (^D))(
List possible completions for the current word.
)
tindex(list-expand)
item(tt(list-expand) (^Xg ^XG) (^G) (^G))(
List the expansion of the current word.
)
tindex(magic-space)
item(tt(magic-space))(
Perform history expansion and insert a space into the
buffer.  This is intended to be bound to space.
)
tindex(menu-complete)
pindex(MENU_COMPLETE, use of)
item(tt(menu-complete))(
Like tt(complete-word), except that menu completion is used.
See the tt(MENU_COMPLETE) option.
)
tindex(menu-expand-or-complete)
item(tt(menu-expand-or-complete))(
Like tt(expand-or-complete), except that menu completion is used.
)
tindex(reverse-menu-complete)
item(tt(reverse-menu-complete))(
Perform menu completion, like tt(menu-complete), except that if
a menu completion is already in progress, move to the em(previous)
completion rather than the next.
)
tindex(end-of-list)
item(tt(end-of-list))(
When a previous completion displayed a list below the prompt, this
widget can be used to move the prompt below the list.
)
enditem()
texinode(Miscellaneous)()(Completion)(Zle Widgets)
subsect(Miscellaneous)
startitem()
tindex(accept-and-hold)
item(tt(accept-and-hold) (ESC-A ESC-a) (unbound) (unbound))(
Push the contents of the buffer on the buffer stack
and execute it.
)
tindex(accept-and-infer-next-history)
item(tt(accept-and-infer-next-history))(
Execute the contents of the buffer.
Then search the history list for a line matching the current one
and push the event following onto the buffer stack.
)
tindex(accept-line)
item(tt(accept-line) (^J ^M) (^J ^M) (^J ^M))(
Finish editing the buffer.  Normally this causes the buffer to be
executed as a shell command.
)
tindex(accept-line-and-down-history)
item(tt(accept-line-and-down-history) (^O) (unbound) (unbound))(
Execute the current line, and push the next history
event on the the buffer stack.
)
tindex(auto-suffix-remove)
item(tt(auto-suffix-remove))(
If the previous action added a suffix (space, slash, etc.) to the word on
the command line, remove it.  Otherwise do nothing.  Removing the suffix
ends any active menu completion or menu selection.

This widget is intended to be called from user-defined widgets to enforce
a desired suffix-removal behavior.
)
tindex(auto-suffix-retain)
item(tt(auto-suffix-retain))(
If the previous action added a suffix (space, slash, etc.) to the word on
the command line, force it to be preserved.  Otherwise do nothing.
Retaining the suffix ends any active menu completion or menu selection.

This widget is intended to be called from user-defined widgets to enforce
a desired suffix-preservation behavior.
)
tindex(beep)
item(tt(beep))(
Beep, unless the tt(BEEP) option is unset.
)
tindex(vi-cmd-mode)
item(tt(vi-cmd-mode) (^X^V) (unbound) (^[))(
Enter command mode; that is, select the `tt(vicmd)' keymap.
Yes, this is bound by default in emacs mode.
)
tindex(vi-caps-lock-panic)
item(tt(vi-caps-lock-panic))(
Hang until any lowercase key is pressed.
This is for vi users without the mental capacity to keep
track of their caps lock key (like the author).
)
tindex(clear-screen)
item(tt(clear-screen) (^L ESC-^L) (^L) (^L))(
Clear the screen and redraw the prompt.
)
tindex(describe-key-briefly)
item(tt(describe-key-briefly))(
Reads a key sequence, then prints the function bound to that sequence.
)
tindex(exchange-point-and-mark)
item(tt(exchange-point-and-mark) (^X^X) (unbound) (unbound))(
Exchange the cursor position (point) with the position of the mark.
Unless a negative prefix argument is given, the region between
point and mark is activated so that it can be highlighted.
If a zero prefix argument is given, the region is activated but
point and mark are not swapped.
)
tindex(execute-named-cmd)
item(tt(execute-named-cmd) (ESC-x) (unbound) (unbound))(
Read the name of an editor command and
execute it.  A restricted set of editing functions is available in the
mini-buffer.  An interrupt signal, as defined by the stty setting, will
abort the function. The allowed functions are:
tt(backward-delete-char),
tt(vi-backward-delete-char),
tt(clear-screen),
tt(redisplay),
tt(quoted-insert),
tt(vi-quoted-insert),
tt(backward-kill-word),
tt(vi-backward-kill-word),
tt(kill-whole-line),
tt(vi-kill-line),
tt(backward-kill-line),
tt(list-choices),
tt(delete-char-or-list),
tt(complete-word),
tt(accept-line),
tt(expand-or-complete) and
tt(expand-or-complete-prefix).

tt(kill-region) kills the last word,
and vi-cmd-mode is treated the same as accept-line.
The space and tab characters, if not bound to one of
these functions, will complete the name and then list the
possibilities if the tt(AUTO_LIST) option is set.
Any other character that is not bound to tt(self-insert) or
tt(self-insert-unmeta) will beep and be ignored.
The bindings of the current insert mode will be used.

Currently this command may not be redefined or called by name.
)
tindex(execute-last-named-cmd)
item(tt(execute-last-named-cmd) (ESC-z) (unbound) (unbound))(
Redo the last function executed with tt(execute-named-cmd).

Currently this command may not be redefined or called by name.
)
tindex(get-line)
item(tt(get-line) (ESC-G ESC-g) (unbound) (unbound))(
Pop the top line off the buffer stack and insert it at the
cursor position.
)
tindex(pound-insert)
item(tt(pound-insert) (unbound) (#) (unbound))(
If there is no # character at the beginning of the buffer,
add one to the beginning of each line.
If there is one, remove a # from each line that has one.
In either case, accept the current line.
The tt(INTERACTIVE_COMMENTS) option must be set
for this to have any usefulness.
)
tindex(vi-pound-insert)
item(tt(vi-pound-insert))(
If there is no # character at the beginning of the current line,
add one.  If there is one, remove it.
The tt(INTERACTIVE_COMMENTS) option must be set
for this to have any usefulness.
)
tindex(push-input)
item(tt(push-input))(
Push the entire current multiline construct onto the buffer stack and
return to the top-level (tt(PS1)) prompt.
If the current parser construct is only a single line, this is exactly
like tt(push-line).
Next time the editor starts up or is popped with tt(get-line), the
construct will be popped off the top of the buffer stack and loaded
into the editing buffer.
)
tindex(push-line)
item(tt(push-line) (^Q ESC-Q ESC-q) (unbound) (unbound))(
Push the current buffer onto the buffer stack and clear
the buffer.
Next time the editor starts up, the buffer will be popped
off the top of the buffer stack and loaded into the editing
buffer.
)
tindex(push-line-or-edit)
item(tt(push-line-or-edit))(
At the top-level (tt(PS1)) prompt, equivalent to tt(push-line).
At a secondary (tt(PS2)) prompt, move the entire current multiline
construct into the editor buffer.
The latter is equivalent to tt(push-input) followed by tt(get-line).
)
tindex(read-command)
item(tt(read-command))(
Only useful from a user-defined widget.  A keystroke is read just as in
normal operation, but instead of the command being executed the name
of the command that would be executed is stored in the shell parameter
tt(REPLY).  This can be used as the argument of a future tt(zle)
command.  If the key sequence is not bound, status 1 is returned;
typically, however, tt(REPLY) is set to tt(undefined-key) to indicate
a useless key sequence.
)
tindex(recursive-edit)
item(tt(recursive-edit))(
Only useful from a user-defined widget.  At this point in the function,
the editor regains control until one of the standard widgets which would
normally cause zle to exit (typically an tt(accept-line) caused by
hitting the return key) is executed.  Instead, control returns to the
user-defined widget.  The status returned is non-zero if the return was
caused by an error, but the function still continues executing and hence
may tidy up.  This makes it safe for the user-defined widget to alter
the command line or key bindings temporarily.


The following widget, tt(caps-lock), serves as an example.
example(self-insert-ucase+LPAR()RPAR() {
  LBUFFER+=${(U)KEYS[-1]}
}

integer stat

zle -N self-insert self-insert-ucase
zle -A caps-lock save-caps-lock
zle -A accept-line caps-lock

zle recursive-edit
stat=$?

zle -A .self-insert self-insert
zle -A save-caps-lock caps-lock
zle -D save-caps-lock

(( stat )) && zle send-break

return $stat
)
This causes typed letters to be inserted capitalised until either
tt(accept-line) (i.e. typically the return key) is typed or the
tt(caps-lock) widget is invoked again; the later is handled by saving
the old definition of tt(caps-lock) as tt(save-caps-lock) and then
rebinding it to invoke tt(accept-line).  Note that an error from the
recursive edit is detected as a non-zero return status and propagated by
using the tt(send-break) widget.
)
tindex(redisplay)
item(tt(redisplay) (unbound) (^R) (^R))(
Redisplays the edit buffer.
)
tindex(reset-prompt)
item(tt(reset-prompt) (unbound) (unbound) (unbound))(
Force the prompts on both the left and right of the screen to be
re-expanded, then redisplay the edit buffer.  This
reflects changes both to the prompt variables themselves and changes
in the expansion of the values (for example, changes in time or
directory, or changes to the value of variables referred to by the
prompt).

Otherwise, the prompt is only expanded each time zle starts, and
when the display as been interrupted by output from another part of the
shell (such as a job notification) which causes the command line to be
reprinted.
)
tindex(send-break)
item(tt(send-break) (^G ESC-^G) (unbound) (unbound))(
Abort the current editor function, e.g. tt(execute-named-command), or the
editor itself, e.g. if you are in tt(vared). Otherwise abort the parsing of
the current line.
)
tindex(run-help)
item(tt(run-help) (ESC-H ESC-h) (unbound) (unbound))(
Push the buffer onto the buffer stack, and execute the
command `tt(run-help) var(cmd)', where var(cmd) is the current
command.  tt(run-help) is normally aliased to tt(man).
)
tindex(vi-set-buffer)
item(tt(vi-set-buffer) (unbound) (") (unbound))(
Specify a buffer to be used in the following command.
There are 35 buffers that can be specified:
the 26 `named' buffers tt("a) to tt("z)
and the nine `queued' buffers tt("1) to tt("9).  The named buffers can also
be specified as tt("A) to tt("Z).

When a buffer is specified for a cut command, the text being cut replaces
the previous contents of the specified buffer.  If a named buffer
is specified using a capital, the newly cut text is appended to the buffer
instead of overwriting it.

If no buffer is specified for a cut command, tt("1) is used, and the
contents of tt("1) to tt("8) are each shifted along one buffer; the contents of
tt("9) is lost.
)
tindex(vi-set-mark)
item(tt(vi-set-mark) (unbound) (m) (unbound))(
Set the specified mark at the cursor position.
)
tindex(set-mark-command)
item(tt(set-mark-command) (^@) (unbound) (unbound))(
Set the mark at the cursor position.  If called with a negative
prefix argument, do not set the mark but deactivate the region so that
it is no longer highlighted (it is still usable for other purposes).
Otherwise the region is marked as active.
)
tindex(spell-word)
item(tt(spell-word) (ESC-$ ESC-S ESC-s) (unbound) (unbound))(
Attempt spelling correction on the current word.
)
tindex(undefined-key)
item(tt(undefined-key))(
This command is executed when a key sequence that is not bound to any
command is typed.  By default it beeps.
)
tindex(undo)
item(tt(undo) (^_ ^Xu ^X^U) (unbound) (unbound))(
Incrementally undo the last text modification.
)
tindex(redo)
item(tt(redo))(
Incrementally redo undone text modifications.
)
tindex(vi-undo-change)
item(tt(vi-undo-change) (unbound) (u) (unbound))(
Undo the last text modification.
If repeated, redo the modification.
)
tindex(what-cursor-position)
item(tt(what-cursor-position) (^X=) (unbound) (unbound))(
Print the character under the cursor, its code as an octal, decimal and
hexadecimal number, the current cursor position within the buffer and the
column of the cursor in the current line.
)
tindex(where-is)
item(tt(where-is))(
Read the name of an editor command and and print the listing of key
sequences that invoke the specified command.
)
tindex(which-command)
item(tt(which-command) (ESC-?) (unbound) (unbound))(
Push the buffer onto the buffer stack, and execute the
command `tt(which-command) var(cmd)'. where var(cmd) is the current
command.  tt(which-command) is normally aliased to var(whence).
)
tindex(vi-digit-or-beginning-of-line)
item(tt(vi-digit-or-beginning-of-line) (unbound) (0) (unbound))(
If the last command executed was a digit as part of an argument,
continue the argument.  Otherwise, execute vi-beginning-of-line.
)
enditem()

texinode(Character Highlighting)()(Zle Widgets)(Zsh Line Editor)
sect(Character Highlighting)

The line editor has the ability to highlight characters or regions
of the line that have a particular significance.  This is controlled
by the array parameter tt(zle_highlight), if it has been set by the user.

If the parameter contains the single entry tt(none) all highlighting
is turned off.  Note the parameter is still expected to be an array.

Otherwise each entry of the array should consist of a word indicating a
context for highlighting, then a colon, then a comma-separated list of
the types of highlighting to apply in that context.

The contexts available for highlighting are the following:

startitem()
cindex(region, highlighting)
cindex(highlighting, region)
item(tt(default))(
Any text within the command line not affected by any other highlighting.
Text outside the editable area of the command line is not affected.
)
item(tt(isearch))(
When one of the incremental history search widgets is active, the
area of the command line matched by the search string or pattern.
)
item(tt(region))(
The region between the cursor (point) and the mark as set with
tt(set-mark-command).  The region is only highlighted if it is active,
which is the case if tt(set-mark-command) or tt(exchange-point-and-mark)
has been called and the line has not been subsequently modified.  The
region can be deactivated by calling tt(set-mark-command) with a
negative prefix argument, or reactivated by calling
tt(exchange-point-and-mark) with a zero prefix argument.  Note
that whether or not the region is active has no effect on its
use within widgets, it simply determines whether it is highlighted.
)
cindex(special characters, highlighting)
cindex(highlighting, special characters)
item(tt(special))(
Individual characters that have no direct printable
representation but are shown in a special manner by the line editor.
These characters are described below.
)
enditem()

tt(zle_highlight) may contain additional fields for controlling how
terminal sequences to change colours are output.  Each of the following is
followed by a colon and a string in the same form as for key bindings.
This will not be necessary for the vast majority of terminals as the
defaults shown in parentheses are widely used.

startitem()
cindex(escape sequences, terminal, for highlighting)
cindex(terminal escape sequences for highlighting)
item(tt(fg_start_code) (tt(\e[3)))(
The start of the escape sequence for the foreground colour.
This is followed by an ASCII digit representing the colour.
)
item(tt(fg_default_code) (tt(9)))(
The number to use instead of the colour to reset the default foreground
colour.
)
item(tt(fg_end_code) (tt(m)))(
The end of the escape sequence for the foreground colour.
)
item(tt(bg_start_code) (tt(\e[4)))(
The start of the escape sequence for the background colour.
This is followed by an ASCII digit representing the colour.
)
item(tt(bg_default_code) (tt(9)))(
The number to use instead of the colour to reset the default
background colour.
)
item(tt(bg_end_code) (tt(m)))(
The end of the escape sequence for the background colour.
)
enditem()

The available types of highlighting are the following.  Note that
not all types of highlighting are available on all terminals:

startitem()
item(tt(none))(
No highlighting is applied to the given context.  It is not useful for
this to appear with other types of highlighting; it is used to override
a default.
)
item(tt(fg=)var(colour))(
The foreground colour should be set to var(colour), a decimal integer
or the name of one of the eight most widely-supported colours.

Not all terminals support this and, of those that do, not all provide
facilities to test the support, hence the user should decide based on the
terminal type.  Most terminals with colour support accept the numbers 0 to
7, and may generate additional colours if the tt(bold) attributes is also
present.  Most terminals also have a standard range of colours for those
numbers (though the interpretation of the colour can vary); these colours
can be set by one of the names tt(black), tt(red), tt(green), tt(yellow),
tt(blue), tt(magenta), tt(cyan) and tt(white).  Abbreviations are
allowed; tt(b) or tt(bl) selects black.

On recent terminals and on systems with an up-to-date terminal database the
number of colours supported may be tested by with the command `tt(echotc
Co)'; if this succeeds, it indicates a limit on the number of colours which
will be enforced by the line editor.  The number of colours is in case
limited to 256 (i.e. the range 0 to 255).

Colour is also known as color.
)
item(tt(bg=)var(colour))(
The background colour should be set to var(colour).
This works similarly to the foreground colour, except the background is
not usually affected by the bold attribute.
)
item(tt(bold))(
The characters in the given context are shown in a bold font.
)
item(tt(standout))(
The characters in the given context are shown in the terminal's standout
mode.  The actual effect is specific to the terminal; on many terminals it
is inverse video.  On some such terminals, where the cursor does not blink
it appears with standout mode negated, making it less than clear where
the cursor actually is.  On such terminals one of the other effects
may be preferable for highlighting the region and matched search string.
)
item(tt(underline))(
The characters in the given context are shown underlined.  Some
terminals show the foreground in a different colour instead; in this
case whitespace will not be highlighted.
)
enditem()

The characters described above as `special' are as follows.  The
formatting described here is used irrespective of whether the characters
are highlighted:

startitem()
item(ASCII control characters)(
Control characters in the ASCII range are shown as
`tt(^)' followed by the base character.
)
item(Unprintable multibyte characters)(
This item applies to control characters not in the ASCII range,
plus other characters as follows.  If the tt(MULTIBYTE) option is in
effect, multibyte characters not in the ASCII character set that are
reported as having zero width are treated as combining characters when the
option tt(COMBINING_CHARS) is on.  If the option is off, or if a character
appears where a combining character is not valid, the character
is treated as unprintable.

Unprintable multibyte characters are shown as a hexadecimal number between
angle brackets.  The number is the code point of the character in the wide
character set; this may or may not be Unicode, depending on the operating
system.
)
enditem()

If tt(zle_highlight) is not set or no value applies to a particular
context, the defaults applied are equivalent to

example(zle_highlight=LPAR()region:standout special:standout
isearch:underline+RPAR())

i.e. both the region and special characters are shown in standout mode.

Within widgets, arbitrary regions may be highlighted by setting the
special array parameter tt(region_highlight); see
ifnzman(noderef(Zle Widgets))\
ifzman(above).