.. historic nodename: Completion Using compctl

Completion Using compctl
================================================================================
.. index:: single: completion, programmable; Command

.. index:: single: completion, controlling; Command

.. only:: man

    Description
    --------------------------------------------------------------------------------
    .. index:: single: compctl; Function
    
    
    This version of zsh has two ways of performing completion of words on the
    command line.  New users of the shell may prefer to use the newer
    and more powerful system based on shell functions; this is described in
    :manpage:`zshcompsys(1)`, and the basic shell mechanisms which support it are
    described in :manpage:`zshcompwid(1)`.  This manual entry describes the older
    ``compctl`` command.
    

.. only:: not man

    Types of completion
    --------------------------------------------------------------------------------
    This version of zsh has two ways of performing completion of words on the
    command line.  New users of the shell may prefer to use the newer
    and more powerful system based on shell functions; this is described
    in :ref:`Completion System`, and the basic shell mechanisms which support
    it are described in :ref:`Completion Widgets`.  This chapter describes
    the older ``compctl`` command.
    Description
    --------------------------------------------------------------------------------
    .. index:: single: compctl; Function
    
    
    

    
    * ``compctl`` [ ``-CDT`` ] :var:`options` [ :var:`command` ... ]
    * ``compctl`` [ ``-CDT`` ] :var:`options` [ ``-x`` :var:`pattern` :var:`options` ``-`` ... ``--`` ]
    *         [ ``+`` :var:`options` [ ``-x`` ... ``--`` ] ... [``+``] ] [ :var:`command` ... ]
    * ``compctl`` ``-M`` :var:`match-specs` ...
    * ``compctl`` ``-L`` [ ``-CDTM`` ] [ :var:`command` ... ]
    * ``compctl`` ``+`` :var:`command` ...

Control the editor's completion behavior according to the supplied set
of :var:`options`.  Various editing commands, notably
``expand-or-complete-word``, usually bound to tab, will
attempt to complete a word typed by the user, while others, notably
``delete-char-or-list``, usually bound to ^D in EMACS editing
mode, list the possibilities; ``compctl`` controls what those
possibilities are.  They may for example be filenames (the most common
case, and hence the default), shell variables, or words from a
user-specified list.

.. historic nodename: Command Flags

Command Flags
--------------------------------------------------------------------------------
Completion of the arguments of a command may be different for each
command or may use the default.  The behavior when completing the
command word itself may also be separately specified.  These
correspond to the following flags and arguments, all of which (except
for ``-L``) may be combined with any combination of the
:var:`options` described subsequently in :ref:`Option Flags`:

:var:`command` ...
    
    controls completion for the named commands, which must be listed last
    on the command line.  If completion is attempted for a command with a
    pathname containing slashes and no completion definition is found, the
    search is retried with the last pathname component. If the command starts
    with a ``=``, completion is tried with the pathname of the command.
    
    Any of the :var:`command` strings may be patterns of the form normally
    used for filename generation.  These should be quoted to protect them
    from immediate expansion; for example the command string ``'foo*'``
    arranges for completion of the words of any command beginning with
    ``foo``.  When completion is attempted, all pattern completions are
    tried in the reverse order of their definition until one matches.  By
    default, completion then proceeds as normal, i.e. the shell will try to
    generate more matches for the specific command on the command line; this
    can be overridden by including ``-tn`` in the flags for the pattern
    completion.
    
    Note that aliases
    are expanded before the command name is determined unless the
    ``COMPLETE_ALIASES`` option is set.  Commands may not be combined
    with the ``-C``, ``-D`` or ``-T`` flags.
    

``-C``
    
    controls completion when the command word itself is being completed.
    If no ``compctl -C`` command has been issued,  the names of any
    executable command (whether in the path or specific to the shell, such
    as aliases or functions) are completed.
    

``-D``
    
    controls default completion behavior for the arguments of commands not
    assigned any special behavior.  If no ``compctl -D`` command has
    been issued, filenames are completed.
    

``-T``
    
    supplies completion flags to be used before any other processing is
    done, even before processing for ``compctl``\s defined for specific
    commands.  This is especially useful when combined with extended
    completion (the ``-x`` flag, see :ref:`Extended Completion` below).
    Using this flag you can define default behavior
    which will apply to all commands without exception, or you can alter
    the standard behavior for all commands.  For example, if your access
    to the user database is too slow and/or it contains too many users (so
    that completion after ``~`` is too slow to be usable), you can use
    
    
    .. code-block:: zsh
       :class: example

        compctl -T -x 's[~] C[0,[^/]#]' -k friends -S/ -tn
    
    
    to complete the strings in the array ``friends`` after a ``~``.
    The ``C[``:var:`...`\ ``]`` argument is necessary so that this form of
    ``~``-completion is
    not tried after the directory name is finished.
    

``-L``
    
    lists the existing completion behavior in a manner suitable for
    putting into a start-up script; the existing behavior is not changed.
    Any combination of the above forms, or the ``-M`` flag (which must
    follow the ``-L`` flag), may be specified, otherwise all defined
    completions are listed.  Any other flags supplied are ignored.
    

:emphasis:`no argument`
    
    If no argument is given, ``compctl`` lists all defined completions
    in an abbreviated form;  with a list of :var:`options`, all completions
    with those flags set (not counting extended completion) are listed.
    

If the ``+`` flag is alone and followed immediately by the :var:`command`
list, the completion behavior for all the commands in the list is reset to
the default.  In other words, completion will subsequently use the
options specified by the ``-D`` flag.

The form with ``-M`` as the first and only option defines global
matching specifications (see :zshsectref:`Completion Matching Control <zshcompwid>`).
The match specifications given will be used for every completion
attempt (only when using ``compctl``, not with the new completion
system) and are tried in the order in which they are defined until one 
generates at least one match. E.g.:

.. code-block:: zsh
   :class: example

    compctl -M '' 'm:{a-zA-Z}={A-Za-z}'

This will first try completion without any global match specifications 
(the empty string) and, if that generates no matches, will try case
insensitive completion.

.. historic nodename: Option Flags

Option Flags
--------------------------------------------------------------------------------
    
    * [ ``-fcFBdeaRGovNAIOPZEnbjrzu/12`` ]
    * [ ``-k`` :var:`array` ] [ ``-g`` :var:`globstring` ] [ ``-s`` :var:`subststring` ]
    * [ ``-K`` :var:`function` ]
    * [ ``-Q`` ] [ ``-P`` :var:`prefix` ] [ ``-S`` :var:`suffix` ]
    * [ ``-W`` :var:`file-prefix` ] [ ``-H`` :var:`num pattern` ]
    * [ ``-q`` ] [ ``-X`` :var:`explanation` ] [ ``-Y`` :var:`explanation` ]
    * [ ``-y`` :var:`func-or-var` ] [ ``-l`` :var:`cmd` ] [ ``-h`` :var:`cmd` ] [ ``-U`` ]
    * [ ``-t`` :var:`continue` ] [ ``-J`` :var:`name` ] [ ``-V`` :var:`name` ]
    * [ ``-M`` :var:`match-spec` ]

The remaining :var:`options` specify the type of command arguments
to look for during completion.  Any combination of these flags may be
specified; the result is a sorted list of all the possibilities.  The
options are as follows.

.. historic nodename: Simple Flags

Simple Flags
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
These produce completion lists made up by the shell itself:

``-f``
    
    Filenames and file system paths.
    

``-/``
    
    Just file system paths.
    

``-c``
    
    Command names, including aliases, shell functions, builtins
    and reserved words.
    

``-F``
    
    Function names.
    

``-B``
    
    Names of builtin commands.
    

``-m``
    
    Names of external commands.
    

``-w``
    
    Reserved words.
    

``-a``
    
    Alias names.
    

``-R``
    
    Names of regular (non-global) aliases.
    

``-G``
    
    Names of global aliases.
    

``-d``
    
    This can be combined with ``-F``, ``-B``, ``-w``,
    ``-a``, ``-R`` and ``-G`` to get names of disabled
    functions, builtins, reserved words or aliases.
    

``-e``
    
    This option (to show enabled commands) is in effect by default, but
    may be combined with ``-d``; ``-de`` in combination with
    ``-F``, ``-B``, ``-w``, ``-a``, ``-R`` and ``-G``
    will complete names of functions, builtins, reserved words or aliases
    whether or not they are disabled.
    

``-o``
    
    Names of shell options (see :manpage:`zshoptions`).
    

``-v``
    
    Names of any variable defined in the shell.
    

``-N``
    
    Names of scalar (non-array) parameters.
    

``-A``
    
    Array names.
    

``-I``
    
    Names of integer variables.
    

``-O``
    
    Names of read-only variables.
    

``-p``
    
    Names of parameters used by the shell (including special parameters).
    

``-Z``
    
    Names of shell special parameters.
    

``-E``
    
    Names of environment variables.
    

``-n``
    
    Named directories.
    

``-b``
    
    Key binding names.
    

``-j``
    
    Job names:  the first word of the job leader's command line.  This is useful
    with the ``kill`` builtin.
    

``-r``
    
    Names of running jobs.
    

``-z``
    
    Names of suspended jobs.
    

``-u``
    
    User names.
    

.. historic nodename: Flags with Arguments

Flags with Arguments
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
These have user supplied arguments to determine how the list of
completions is to be made up:

``-k`` :var:`array`
    
    Names taken from the elements of ``$``:var:`array` (note that the ``$``
    does not appear on the command line).
    Alternatively, the argument :var:`array` itself may be a set
    of space- or comma-separated values in parentheses, in which any
    delimiter may be escaped with a backslash; in this case the argument
    should be quoted.  For example,
    
    
    .. code-block:: zsh
       :class: example

        compctl -k "(cputime filesize datasize stacksize
        	       coredumpsize resident descriptors)" limit
    
    

``-g`` :var:`globstring`
    
    The :var:`globstring` is expanded using filename globbing; it should be
    quoted to protect it from immediate expansion. The resulting
    filenames are taken as the possible completions.  Use ``*(/)`` instead of
    ``*/`` for directories.  The ``fignore`` special parameter is not
    applied to the resulting files.  More than one pattern may be given
    separated by blanks. (Note that brace expansion is :emphasis:`not` part of
    globbing.  Use the syntax ``(either|or)`` to match alternatives.)
    

``-s`` :var:`subststring`
    
    The :var:`subststring` is split into words and these words are than
    expanded using all shell expansion mechanisms (see
    :manpage:`zshexpn`).
    The resulting words are taken as possible
    completions.  The ``fignore`` special parameter is not applied to the
    resulting files.  Note that ``-g`` is faster for filenames.
    

``-K`` :var:`function`
    
    .. index:: single: reply, use of; Variable
    
    
    Call the given function to get the completions.  Unless the name
    starts with an underscore, the function is
    passed two arguments: the prefix and the suffix of the word on which
    completion is to be attempted, in other words those characters before
    the cursor position, and those from the cursor position onwards.  The
    whole command line can be accessed with the ``-c`` and ``-l`` flags
    of the ``read`` builtin. The
    function should set the variable ``reply`` to an array containing
    the completions (one completion per element); note that ``reply``
    should not be made local to the function.  From such a function the
    command line can be accessed with the ``-c`` and ``-l`` flags to
    the ``read`` builtin.  For example,
    
    
    .. code-block:: zsh
       :class: example

        function whoson { reply=(`users`); }
        compctl -K whoson talk
    
    
    completes only logged-on users after ``talk``.  Note that ``whoson`` must
    return an array, so ```reply=`users\``\`' would be incorrect.
    

``-H`` :var:`num pattern`
    
    The possible completions are taken from the last :var:`num` history
    lines.  Only words matching :var:`pattern` are taken.  If :var:`num` is
    zero or negative the whole history is searched and if :var:`pattern` is
    the empty string all words are taken (as with ``*``).  A typical
    use is
    
    
    .. code-block:: zsh
       :class: example

        compctl -D -f + -H 0 ''
    
    
    which forces completion to look back in the history list for a word if
    no filename matches.
    

.. historic nodename: Control Flags

Control Flags
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
These do not directly specify types of name to be completed, but
manipulate the options that do:

``-Q``
    
    This instructs the shell not to quote any metacharacters in the possible
    completions.  Normally the results of a completion are inserted into
    the command line with any metacharacters quoted so that they are
    interpreted as normal characters.  This is appropriate for filenames
    and ordinary strings.  However, for special effects, such as inserting
    a backquoted expression from a completion array (``-k``) so that
    the expression will not be evaluated until the complete line is
    executed, this option must be used.
    

``-P`` :var:`prefix`
    
    The :var:`prefix` is inserted just before the completed string; any
    initial part already typed will be completed and the whole :var:`prefix`
    ignored for completion purposes.  For example,
    
    
    .. code-block:: zsh
       :class: example

        compctl -j -P "%" kill
    
    
    inserts a \`%' after the kill command and then completes job names.
    

``-S`` :var:`suffix`
    
    When a completion is found the :var:`suffix` is inserted after
    the completed string.  In the case of menu completion the suffix is
    inserted immediately, but it is still possible to cycle through the
    list of completions by repeatedly hitting the same key.
    

``-W`` :var:`file-prefix`
    
    With directory :var:`file-prefix`:  for command, file, directory and
    globbing completion (options ``-c``, ``-f``, ``-/``, ``-g``), the file
    prefix is implicitly added in front of the completion.  For example,
    
    
    .. code-block:: zsh
       :class: example

        compctl -/ -W ~/Mail maildirs
    
    
    completes any subdirectories to any depth beneath the directory
    ``~/Mail``, although that prefix does not appear on the command line.
    The :var:`file-prefix` may also be of the form accepted by the ``-k``
    flag, i.e. the name of an array or a literal list in parenthesis. In
    this case all the directories in the list will be searched for
    possible completions.
    

``-q``
    
    If used with a suffix as specified by the ``-S`` option, this
    causes the suffix to be removed if the next character typed is a blank
    or does not insert anything or if the suffix consists of only one character
    and the next character typed is the same character; this the same rule used
    for the ``AUTO_REMOVE_SLASH`` option.  The option is most useful for list
    separators (comma, colon, etc.).
    

``-l`` :var:`cmd`
    
    This option restricts the range
    of command line words that are considered to be arguments.  If
    combined with one of the extended completion patterns ``p[...]``,
    ``r[...]``, or ``R[...]``  (see :ref:`Extended Completion`
    below) the range is restricted to the range of arguments
    specified in the brackets.  Completion is then performed as if these
    had been given as arguments to the :var:`cmd` supplied with the
    option. If the :var:`cmd` string is empty the first word in the range
    is instead taken as the command name, and command name completion
    performed on the first word in the range.  For example,
    
    
    .. code-block:: zsh
       :class: example

        compctl -x 'r[-exec,;]' -l '' -- find
    
    
    completes arguments between ``-exec`` and the following ``;`` (or the end
    of the command line if there is no such string) as if they were
    a separate command line.
    

``-h`` :var:`cmd`
    
    Normally zsh completes quoted strings as a whole. With this option,
    completion can be done separately on different parts of such
    strings. It works like the ``-l`` option but makes the completion code 
    work on the parts of the current word that are separated by
    spaces. These parts are completed as if they were arguments to the
    given :var:`cmd`. If :var:`cmd` is the empty string, the first part is
    completed as a command name, as with ``-l``.
    

``-U``
    
    Use the whole list of possible completions, whether or not they
    actually match the word on the command line.  The word typed so far
    will be deleted.  This is most useful with a function (given by the
    ``-K`` option) which can examine the word components passed to it
    (or via the ``read`` builtin's ``-c`` and ``-l`` flags) and
    use its own criteria to decide what matches.  If there is no
    completion, the original word is retained.  Since the produced 
    possible completions seldom have interesting common prefixes
    and suffixes, menu completion is started immediately if ``AUTO_MENU`` is
    set and this flag is used.
    

``-y`` :var:`func-or-var`
    
    .. index:: single: reply, use of; Variable
    
    
    The list provided by :var:`func-or-var` is displayed instead of the list
    of completions whenever a listing is required; the actual completions
    to be inserted are not affected.  It can be provided in two
    ways. Firstly, if :var:`func-or-var` begins with a ``$`` it defines a
    variable, or if it begins with a left parenthesis a literal
    array, which contains the list.  A variable may have been set by a
    call to a function using the ``-K`` option.  Otherwise it contains the
    name of a function which will be executed to create the list.  The
    function will be passed as an argument list all matching completions,
    including prefixes and suffixes expanded in full, and should set the
    array ``reply`` to the result.  In both cases, the display list will
    only be retrieved after a complete list of matches has been created.
    
    Note that the returned list does not have to correspond, even in
    length, to the original set of matches, and may be passed as a scalar
    instead of an array.  No special formatting of characters is
    performed on the output in this case; in particular, newlines are
    printed literally and if they appear output in columns is suppressed.
    

``-X`` :var:`explanation`
    
    Print :var:`explanation` when trying completion on the current set of
    options. A ``%n`` in this string is replaced by the number of
    matches that were added for this explanation string.
    The explanation only appears if completion was tried and there was
    no unique match, or when listing completions. Explanation strings 
    will be listed together with the matches of the group specified
    together with the ``-X`` option (using the ``-J`` or ``-V``
    option). If the same explanation string is given to multiple ``-X``
    options, the string appears only once (for each group) and the number
    of matches shown for the ``%n`` is the total number of all matches
    for each of these uses. In any case, the explanation string will only
    be shown if there was at least one match added for the explanation
    string.
    
    The sequences ``%B``, ``%b``, ``%S``, ``%s``, ``%U``, and ``%u`` specify
    output attributes (bold, standout, and underline), ``%F``, ``%f``, ``%K``,
    ``%k`` specify foreground and background colours, and ``%{``:var:`...`\ ``%}`` can
    be used to include literal escape sequences as in prompts.
    

``-Y`` :var:`explanation`
    
    Identical to ``-X``, except that the :var:`explanation` first undergoes
    expansion following the usual rules for strings in double quotes.
    The expansion will be carried out after any functions are called for
    the ``-K`` or ``-y`` options, allowing them to set variables.
    

``-t`` :var:`continue`
    
    The :var:`continue`-string contains a character that specifies which set
    of completion flags should be used next.  It is useful:
    
    (i) With ``-T``, or when trying a list of pattern completions, when
    ``compctl`` would usually continue with ordinary processing after
    finding matches; this can be suppressed with ``-tn``.
    
    (ii) With a list of alternatives separated by ``+``, when ``compctl``
    would normally stop when one of the alternatives generates matches.  It
    can be forced to consider the next set of completions by adding ``-t+``
    to the flags of the alternative before the ``+``.
    
    (iii) In an extended completion list (see below), when ``compctl`` would
    normally continue until a set of conditions succeeded, then use only
    the immediately following flags.  With ``-t-``, ``compctl`` will
    continue trying extended completions after the next ``-``; with
    ``-tx`` it will attempt completion with the default flags, in other
    words those before the ``-x``.
    

``-J`` :var:`name`
    
    This gives the name of the group the matches should be placed in. Groups
    are listed and sorted separately; likewise, menu completion will offer
    the matches in the groups in the order in which the groups were
    defined. If no group name is explicitly given, the matches are stored in
    a group named ``default``. The first time a group name is encountered,
    a group with that name is created. After that all matches with the same
    group name are stored in that group.
    
    This can be useful with non-exclusive alternative completions.  For
    example, in
    
    
    .. code-block:: zsh
       :class: example

        compctl -f -J files -t+ + -v -J variables foo
    
    
    both files and variables are possible completions, as the ``-t+`` forces
    both sets of alternatives before and after the ``+`` to be considered at
    once.  Because of the ``-J`` options, however, all files are listed
    before all variables.
    

``-V`` :var:`name`
    
    Like ``-J``, but matches within the group will not be sorted in listings
    nor in menu completion. These unsorted groups are in a different name
    space from the sorted ones, so groups defined as ``-J files`` and ``-V
    files`` are distinct.
    

``-1``
    
    If given together with the ``-V`` option, makes
    only consecutive duplicates in the group be removed. Note that groups
    with and without this flag are in different name spaces.
    

``-2``
    
    If given together with the ``-J`` or ``-V`` option, makes all
    duplicates be kept. Again, groups with and without this flag are in
    different name spaces.
    

``-M`` :var:`match-spec`
    
    This defines additional matching control specifications that should be used
    only when testing words for the list of flags this flag appears in. The format
    of the :var:`match-spec` string is described in 
    :zshsectref:`Completion Matching Control <zshcompwid>`.
    

.. historic nodename: Alternative Completion

Alternative Completion
--------------------------------------------------------------------------------
    
    * ``compctl`` [ ``-CDT`` ] :var:`options` ``+`` :var:`options` [ ``+`` ... ] [ ``+`` ] :var:`command` ...

The form with ``+`` specifies alternative options. Completion is
tried with the options before the first ``+``. If this produces no
matches completion is tried with the flags after the ``+`` and so on. If
there are no flags after the last ``+`` and a match has not been found
up to that point, default completion is tried.
If the list of flags contains a ``-t`` with a ``+`` character, the next
list of flags is used even if the current list produced matches.

.. historic nodename: Extended Completion

Additional options are available that restrict completion to some part
of the command line; this is referred to as \`extended completion'.

Extended Completion
--------------------------------------------------------------------------------

    
    * ``compctl`` [ ``-CDT`` ] :var:`options` ``-x`` :var:`pattern` :var:`options` ``-`` ... ``--``
    *         [ :var:`command` ... ]
    * ``compctl`` [ ``-CDT`` ] :var:`options` [ ``-x`` :var:`pattern` :var:`options` ``-`` ... ``--`` ]
    *         [ ``+`` :var:`options` [ ``-x`` ... ``--`` ] ... [``+``] ] [ :var:`command` ... ]

The form with ``-x`` specifies extended completion for the
commands given; as shown, it may be combined with alternative
completion using ``+``.  Each :var:`pattern` is examined in turn; when a
match is found, the corresponding :var:`options`, as described in
:ref:`Option Flags` above, are used to generate possible
completions.  If no :var:`pattern` matches, the :var:`options` given
before the ``-x`` are used.

Note that each pattern should be supplied as a single argument and
should be quoted to prevent expansion of metacharacters by the
shell.

A :var:`pattern` is built of sub-patterns separated by commas; it
matches if at least one of these sub-patterns matches (they are
\`or'ed). These sub-patterns are in turn composed of other
sub-patterns separated by white spaces which match if all of the
sub-patterns match (they are \`and'ed).  An element of the
sub-patterns is of the form :var:`c`\ ``[...][...]``, where the pairs of
brackets may be repeated as often as necessary, and matches if any of
the sets of brackets match (an \`or').  The example below makes this
clearer.

The elements may be any of the following:

``s[``:var:`string`\ ``]``...
    
    Matches if the current word on the command line starts with
    one of the strings given in brackets.  The :var:`string` is not removed
    and is not part of the completion.
    

``S[``:var:`string`\ ``]``...
    
    Like ``s[``:var:`string`\ ``]`` except that the :var:`string` is part of the
    completion.
    

``p[``:var:`from`\ ``,``:var:`to`\ ``]``...
    
    Matches if the number of the current word is between one of
    the :var:`from` and :var:`to` pairs inclusive. The comma and :var:`to`
    are optional; :var:`to` defaults to the same value as :var:`from`.  The
    numbers may be negative: ``-``:var:`n` refers to the :var:`n`'th last word
    on the line.
    

``c[``:var:`offset`\ ``,``:var:`string`\ ``]``...
    
    Matches if the :var:`string` matches the word offset by
    :var:`offset` from the current word position.  Usually :var:`offset`
    will be negative.
    

``C[``:var:`offset`\ ``,``:var:`pattern`\ ``]``...
    
    Like ``c`` but using pattern matching instead.
    

``w[``:var:`index`\ ``,``:var:`string`\ ``]``...
    
    Matches if the word in position :var:`index` is equal
    to the corresponding :var:`string`.  Note that the word count is made
    after any alias expansion.
    

``W[``:var:`index`\ ``,``:var:`pattern`\ ``]``...
    
    Like ``w`` but using pattern matching instead.
    

``n[``:var:`index`\ ``,``:var:`string`\ ``]``...
    
    Matches if the current word contains :var:`string`.  Anything up to and
    including the :var:`index`\th occurrence of this string will not be
    considered part of the completion, but the rest will.  :var:`index` may
    be negative to count from the end: in most cases, :var:`index` will be
    1 or -1.  For example,
    
    
    .. code-block:: zsh
       :class: example

        compctl -s '`users`' -x 'n[1,@]' -k hosts -- talk
    
    
    will usually complete usernames, but if you insert an ``@`` after the
    name, names from the array :var:`hosts` (assumed to contain hostnames,
    though you must make the array yourself) will be completed.  Other
    commands such as ``rcp`` can be handled similarly.
    

``N[``:var:`index`\ ``,``:var:`string`\ ``]``...
    
    Like ``n`` except that the string will be
    taken as a character class.  Anything up to and including the
    :var:`index`\th occurrence of any of the characters in :var:`string`
    will not be considered part of the completion.
    

``m[``:var:`min`\ ``,``:var:`max`\ ``]``...
    
    Matches if the total number of words lies between :var:`min` and
    :var:`max` inclusive.
    

``r[``:var:`str1`\ ``,``:var:`str2`\ ``]``...
    
    Matches if the cursor is after a word with prefix :var:`str1`.  If there
    is also a word with prefix :var:`str2` on the command line after the one 
    matched by :var:`str1` it matches
    only if the cursor is before this word. If the comma and :var:`str2` are
    omitted, it matches if the cursor is after a word with prefix :var:`str1`.
    

``R[``:var:`str1`\ ``,``:var:`str2`\ ``]``...
    
    Like ``r`` but using pattern matching instead.
    

``q[``:var:`str`\ ``]``...
    
    Matches the word currently being completed is in single quotes and the 
    :var:`str` begins with the letter \`s', or if completion is done in
    double quotes and :var:`str` starts with the letter \`d', or if
    completion is done in backticks and :var:`str` starts with a \`b'.
    

.. historic nodename: Example

Example
--------------------------------------------------------------------------------

.. code-block:: zsh
   :class: example

    compctl -u -x 's[+] c[-1,-f],s[-f+]' \ 
      -g '~/Mail/*(:t)' - 's[-f],c[-1,-f]' -f -- mail

This is to be interpreted as follows:

If the current command is ``mail``, then

.. 

    
    if ((the current word begins with ``+`` and the previous word is ``-f``)
    or (the current word begins with ``-f+``)), then complete the
    non-directory part (the ``:t`` glob modifier) of files in the directory
    ``~/Mail``; else
    
    if the current word begins with ``-f`` or the previous word was ``-f``, then
    complete any file; else
    
    complete user names.
    

