zshcompwid



ZSHCOMPWID(1)                                                    ZSHCOMPWID(1)




NAME

       zshcompwid - zsh completion widgets


DESCRIPTION

       The shell’s programmable completion mechanism can be manipulated in two
       ways; here the low-level features supporting the newer,  function-based
       mechanism  are  defined.   A  complete  set of shell functions based on
       these features is described in zshcompsys(1), and users with no  inter-
       est  in  adding  to that system (or, potentially, writing their own ---
       see dictionary entry for ‘hubris’) should skip this section.  The older
       system  based  on  the  compctl builtin command is described in zshcom-
       pctl(1).

       Completion widgets are defined by the -C option to the zle builtin com-
       mand provided by the zsh/zle module (see zshzle(1)). For example,

              zle -C complete expand-or-complete completer

       defines  a widget named ‘complete’.  The second argument is the name of
       any of the builtin  widgets  that  handle  completions:  complete-word,
       expand-or-complete,      expand-or-complete-prefix,      menu-complete,
       menu-expand-or-complete,   reverse-menu-complete,   list-choices,    or
       delete-char-or-list.  Note that this will still work even if the widget
       in question has been re-bound.

       When this newly defined widget is bound to  a  key  using  the  bindkey
       builtin  command  defined in the zsh/zle module (see zshzle(1)), typing
       that key will call the shell function  ‘completer’.  This  function  is
       responsible  for  generating  the  possible  matches using the builtins
       described below.  As with other ZLE widgets,  the  function  is  called
       with its standard input closed.

       Once the function returns, the completion code takes over control again
       and treats the matches in the same manner as the specified builtin wid-
       get, in this case expand-or-complete.




SPECIAL PARAMETERS

       Inside  completion  widgets,  and  any functions called from them, some
       parameters have special meaning; outside these functions they  are  not
       special  to  the  shell  in any way.  These parameters are used to pass
       information between the completion code and the completion widget. Some
       of  the builtin commands and the condition codes use or change the cur-
       rent values of these parameters.  Any existing values  will  be  hidden
       during  execution  of  completion  widgets;  except  for compstate, the
       parameters are reset on each function exit (including  nested  function
       calls  from  within  the completion widget) to the values they had when
       the function was entered.

       CURRENT
              This is the number of the current word, i.e. the word the cursor
              is  currently  on  in  the words array.  Note that this value is
              only correct if the ksharrays option is not set.

       IPREFIX
              Initially this will be set to the empty string.  This  parameter
              functions  like  PREFIX; it contains a string which precedes the
              one in PREFIX and is not considered part of the list of matches.
              Typically,  a string is transferred from the beginning of PREFIX
              to the end of IPREFIX, for example:

                     IPREFIX=${PREFIX%%\=*}=
                     PREFIX=${PREFIX#*=}

              causes the part of the prefix up  to  and  including  the  first
              equal  sign not to be treated as part of a matched string.  This
              can be done automatically by the compset builtin, see below.

       ISUFFIX
              As IPREFIX, but for a suffix that should not be considered  part
              of  the matches; note that the ISUFFIX string follows the SUFFIX
              string.

       PREFIX Initially this will be set to the part of the current word  from
              the  beginning  of the word up to the position of the cursor; it
              may be altered to give a common prefix for all matches.

       QIPREFIX
              This parameter is read-only and contains the quoted string up to
              the  word  being  completed.  E.g.  when completing ‘"foo’, this
              parameter contains the double quote. If the -q option of compset
              is used (see below), and the original string was ‘"foo bar’ with
              the cursor on the ‘bar’, this parameter contains ‘"foo ’.

       QISUFFIX
              Like QIPREFIX, but containing the suffix.

       SUFFIX Initially this will be set to the part of the current word  from
              the cursor position to the end; it may be altered to give a com-
              mon suffix for all matches.  It is most useful when  the  option
              COMPLETE_IN_WORD is set, as otherwise the whole word on the com-
              mand line is treated as a prefix.

       compstate
              This is an associative array with various keys and  values  that
              the  completion  code uses to exchange information with the com-
              pletion widget.  The keys are:

              all_quotes
                     The -q option of the compset builtin command (see  below)
                     allows  a quoted string to be broken into separate words;
                     if the cursor is on one of those words, that word will be
                     completed,  possibly  invoking  ‘compset -q’ recursively.
                     With this key it is possible to test the types of  quoted
                     strings  which  are  currently  broken into parts in this
                     fashion.  Its value contains one character for each quot-
                     ing level.  The characters are a single quote or a double
                     quote for strings quoted  with  these  characters  and  a
                     backslash  for  strings not starting with a quote charac-
                     ter.  The first character in the value always corresponds
                     to the innermost quoting level.

              context
                     This  will  be  set by the completion code to the overall
                     context in which completion is attempted. Possible values
                     are:

                     array_value
                             when  completing  inside  the  value  of an array
                             parameter assignment;  in  this  case  the  words
                             array  contains the words inside the parentheses.

                     brace_parameter
                             when completing the name  of  a  parameter  in  a
                             parameter expansion beginning with ${.

                     assign_parameter
                             when  completing  the  name  of  a parameter in a
                             parameter assignment.

                     command
                             when completing for a normal command  (either  in
                             command  position  or for an argument of the com-
                             mand).

                     condition
                             when completing inside  a  ‘[[...]]’  conditional
                             expression; in this case the words array contains
                             only the words inside the conditional expression.

                      math   when  completing  in  a  mathematical environment
                             such as a ‘((...))’ construct.

                     parameter
                             when completing the name  of  a  parameter  in  a
                             parameter  expansion beginning with $ but not ${.

                     redirect
                             when completing after a redirection operator.

                     subscript
                             when completing inside a parameter subscript.

                      value  when completing the value of a parameter  assign-
                             ment.

              exact  Controls  the behaviour when the REC_EXACT option is set.
                     It will be set to accept  if  an  exact  match  would  be
                     accepted, and will be unset otherwise.

                     If it was set when at least one match equal to the string
                     on the line was generated, the match is accepted.

              exact_string
                     The string of an exact match if one was found,  otherwise
                     unset.

              ignored
                     The  number  of  words  that  were  ignored  because they
                     matched one of the patterns given with the -F  option  to
                     the compadd builtin command.

              insert This  controls  the  manner  in which a match is inserted
                     into the command line.  On entry to the widget  function,
                     if  it is unset the command line is not to be changed; if
                     set to unambiguous, any prefix common to all  matches  is
                     to  be inserted; if set to automenu-unambiguous, the com-
                     mon prefix is to be inserted and the next  invocation  of
                     the completion code may start menu completion (due to the
                     AUTO_MENU option being set); if set to menu  or  automenu
                     menu completion will be started for the matches currently
                     generated (in the latter case this  will  happen  because
                     the  AUTO_MENU  is  set).  The value may also contain the
                     string ‘tab’ when the completion code would normally  not
                     really  do completion, but only insert the TAB character.

                     On exit it may be set to any of the values  above  (where
                     setting  it  to the empty string is the same as unsetting
                     it), or to a number, in which case the match whose number
                     is  given  will be inserted into the command line.  Nega-
                     tive numbers count backward from  the  last  match  (with
                     ‘-1’  selecting  the  last match) and out-of-range values
                     are wrapped around, so that a value of zero  selects  the
                     last  match and a value one more than the maximum selects
                     the first. Unless the value of this key ends in a  space,
                     the match is inserted as in a menu completion, i.e. with-
                     out automatically appending a space.

                     Both menu and automenu may also specify the the number of
                     the  match  to insert, given after a colon.  For example,
                     ‘menu:2’ says to start menu  completion,  beginning  with
                     the second match.

                     Note  that  a  value containing the substring ‘tab’ makes
                     the matches generated be ignored  and  only  the  TAB  be
                     inserted.

                     Finally,  it  may  also  be  set  to all, which makes all
                     matches generated be inserted into the line.

              insert_positions
                     When the completion system inserts an unambiguous  string
                     into the line, there may be multiple places where charac-
                     ters are missing or where the character inserted  differs
                     from  at least one match.  The value of this key contains
                     a colon separated list of all these positions, as indexes
                     into the command line.

              last_prompt
                     If  this  is  set  to  a non-empty string for every match
                     added, the completion code will move the cursor  back  to
                     the  previous  prompt  after  the list of completions has
                     been displayed.  Initially this is set or unset according
                     to the ALWAYS_LAST_PROMPT option.

              list   This  controls whether or how the list of matches will be
                     displayed.  If it is unset or empty they  will  never  be
                     listed;  if  its value begins with list, they will always
                     be listed; if it begins with autolist or ambiguous,  they
                     will  be  listed  when  the  AUTO_LIST  or LIST_AMBIGUOUS
                     options respectively would normally cause them to be.

                     If the substring force appears in the value,  this  makes
                     the  list  be shown even if there is only one match. Nor-
                     mally, the list would be shown only if there are at least
                     two matches.

                     The   value   contains   the   substring  packed  if  the
                     LIST_PACKED option is set. If this substring is given for
                     all  matches  added  to a group, this group will show the
                     LIST_PACKED  behavior.  The  same   is   done   for   the
                     LIST_ROWS_FIRST option with the substring rows.

                     Finally,  if  the value contains the string explanations,
                     only the explanation strings, if any, will be listed  and
                     if  it  contains  messages, only the messages (added with
                     the -x option of compadd) will be listed.  If it contains
                     both  explanations and messages both kinds of explanation
                     strings will be listed.  It will be set appropriately  on
                     entry to a completion widget and may be changed there.

              list_lines
                     This gives the number of lines that are needed to display
                     the full list of completions.  Note that to calculate the
                     total number of lines to display you need to add the num-
                     ber of lines needed for the command line to  this  value,
                     this is available as the value of the BUFFERLINES special
                     parameter.

              list_max
                     Initially this is set to the value of the LISTMAX parame-
                     ter.   It  may be set to any other value; when the widget
                     exits this value will be used in  the  same  way  as  the
                     value of LISTMAX.

              nmatches
                     The  number of matches generated and accepted by the com-
                     pletion code so far.

              old_insert
                     On entry to the widget this will be set to the number  of
                     the match of an old list of completions that is currently
                     inserted into the command line.  If  no  match  has  been
                     inserted, this is unset.

                     As with old_list, the value of this key will only be used
                     if it is the string keep. If it was set to this value  by
                     the  widget  and there was an old match inserted into the
                     command line, this match will be kept and if the value of
                     the  insert  key  specifies  that another match should be
                     inserted, this will be inserted after the old one.

              old_list
                     This is set to yes if there is still a valid list of com-
                     pletions  from a previous completion at the time the wid-
                     get is invoked.  This will usually be  the  case  if  and
                     only  if  the previous editing operation was a completion
                     widget or one of the builtin  completion  functions.   If
                     there  is  a valid list and it is also currently shown on
                     the screen, the value of this key is shown.

                     After the widget has exited the value of this key is only
                     used  if it was set to keep.  In this case the completion
                     code will continue to use this old list.  If  the  widget
                     generated new matches, they will not be used.

              parameter
                     The  name of the parameter when completing in a subscript
                     or in the value of a parameter assignment.

              pattern_insert
                     Normally this is set to menu, which specifies  that  menu
                     completion  will  be  used  whenever a set of matches was
                     generated using pattern matching.  If it is  set  to  any
                     other non-empty string by the user and menu completion is
                     not selected by other  option  settings,  the  code  will
                     instead  insert  any  common  prefix  for  the  generated
                     matches as with normal completion.

              pattern_match
                     Locally controls the behaviour given by the GLOB_COMPLETE
                     option.   Initially  it  is set to ‘*’ if and only if the
                     option is set.  The completion widget may set it to  this
                     value,  to  an empty string (which has the same effect as
                     unsetting it), or to any other non-empty string.   If  it
                     is non-empty, unquoted metacharacters on the command line
                     will be treated as patterns; if it is ‘*’, then addition-
                     ally a wildcard ‘*’ is assumed at the cursor position; if
                     it is empty or unset, metacharacters will be treated lit-
                     erally.

                     Note that the matcher specifications given to the compadd
                     builtin command  are  not  used  if  this  is  set  to  a
                     non-empty string.

              quote  When  completing  inside quotes, this contains the quota-
                     tion character (i.e. either  a  single  quote,  a  double
                     quote, or a backtick).  Otherwise it is unset.

              quoting
                     When  completing inside single quotes, this is set to the
                     string single; inside double quotes, the  string  double;
                     inside  backticks,  the string backtick.  Otherwise it is
                     unset.

              redirect
                     The redirection operator when completing in a redirection
                     position, i.e. one of <, >, etc.

              restore
                     This  is  set to auto before a function is entered, which
                     forces the special  parameters  mentioned  above  (words,
                     CURRENT,  PREFIX,  IPREFIX,  SUFFIX,  and  ISUFFIX) to be
                     restored to  their  previous  values  when  the  function
                     exits.    If a function unsets it or sets it to any other
                     string, they will not be restored.

              to_end Specifies the occasions on which the cursor is  moved  to
                     the  end  of a string when a match is inserted.  On entry
                     to a widget function, it may be single if this will  hap-
                     pen when a single unambiguous match was inserted or match
                     if it will happen any time a match is inserted (for exam-
                     ple,  by menu completion; this is likely to be the effect
                     of the ALWAYS_TO_END option).

                     On exit, it may be set to single as above.  It  may  also
                     be  set  to  always,  or to the empty string or unset; in
                     those cases the cursor will be moved to the  end  of  the
                     string always or never respectively.  Any other string is
                     treated as match.

              unambiguous
                     This key is read-only and will always be set to the  com-
                     mon  (unambiguous)  prefix the completion code has gener-
                     ated for all matches added so far.

              unambiguous_cursor
                     This gives the position the cursor would be placed at  if
                     the  common  prefix in the unambiguous key were inserted,
                     relative to the value of that key. The  cursor  would  be
                     placed  before the character whose index is given by this
                     key.

              unambiguous_positions
                     This contains all positions where characters in the unam-
                     biguous   string  are  missing  or  where  the  character
                     inserted differs from at least one of the  matches.   The
                     positions  are  given as indexes into the string given by
                     the value of the unambiguous key.

              vared  If completion is called while editing a  line  using  the
                     vared  builtin,  the value of this key is set to the name
                     of the parameter given as an argument to vared.  This key
                     is only set while a vared command is active.

       words  This  array  contains the words present on the command line cur-
              rently being edited.



BUILTIN COMMANDS

       compadd [ -akqQfenUl12C ] [ -F array ]
       [ -P prefix ] [ -S suffix ]
       [ -p hidden-prefix ] [ -s hidden-suffix ]
       [ -i ignored-prefix ] [ -I ignored-suffix ]
       [ -W file-prefix ] [ -d array ]
       [ -J name ] [ -V name ] [ -X explanation ] [ -x message ]
       [ -r remove-chars ] [ -R remove-func ]
       [ -D array ] [ -O array ] [ -A array ]
       [ -E number ]
       [ -M match-spec ] [ -- ] [ words ... ]

              This builtin command can be used to  add  matches  directly  and
              control all the information the completion code stores with each
              possible match. The return value is zero if at least  one  match
              was added and non-zero if no matches were added.

              The  completion  code  breaks  the string to complete into seven
              fields in the order:

                     <ipre><apre><hpre><word><hsuf><asuf><isuf>

              The first field is an ignored  prefix  taken  from  the  command
              line,  the  contents  of  the  IPREFIX parameter plus the string
              given with the -i option. With the -U option,  only  the  string
              from the -i option is used. The field <apre> is an optional pre-
              fix string given with the -P option.   The  <hpre>  field  is  a
              string  that is considered part of the match but that should not
              be shown when listing completions, given with the -p option; for
              example,  functions  that do filename generation might specify a
              common path prefix this way.  <word> is the part  of  the  match
              that  should  appear in the list of completions, i.e. one of the
              words given at the end of the compadd command line. The suffixes
              <hsuf>,  <asuf>  and  <isuf>  correspond to the prefixes <hpre>,
              <apre> and <ipre> and are given by the options -s,  -S  and  -I,
              respectively.

              The supported flags are:

              -P prefix
                     This  gives  a  string  to  be  inserted before the given
                     words.  The string given is not considered as part of the
                     match  and  any  shell  metacharacters  in it will not be
                     quoted when the string is inserted.

              -S suffix
                     Like -P, but gives a string  to  be  inserted  after  the
                     match.

              -p hidden-prefix
                     This gives a string that should be inserted into the com-
                     mand line before the match but that should not appear  in
                     the  list of matches. Unless the -U option is given, this
                     string must be matched as part of the string on the  com-
                     mand line.

              -s hidden-suffix
                     Like  ‘-p’, but gives a string to insert after the match.

              -i ignored-prefix
                     This gives a string to insert into the command line  just
                     before  any  string  given with the ‘-P’ option.  Without
                     ‘-P’ the string is inserted before the string given  with
                     ‘-p’ or directly before the match.

              -I ignored-suffix
                     Like -i, but gives an ignored suffix.

              -a     With this flag the words are taken as names of arrays and
                     the possible matches are their values.  If only some ele-
                     ments  of  the arrays are needed, the words may also con-
                     tain subscripts, as in ‘foo[2,-1]’.

              -k     With this flag the words are taken as names  of  associa-
                     tive  arrays and the possible matches are their keys.  As
                     for -a, the words may  also  contain  subscripts,  as  in
                     ‘foo[(R)*bar*]’.

              -d array
                     This  adds  per-match  display  strings. The array should
                     contain one element per word given. The  completion  code
                     will  then display the first element instead of the first
                     word, and so on. The array may be given as the name of an
                     array  parameter or directly as a space-separated list of
                     words in parentheses.

                     If there are fewer display strings than words, the  left-
                     over  words  will be displayed unchanged and if there are
                     more display strings than  words,  the  leftover  display
                     strings will be silently ignored.

              -l     This  option only has an effect if used together with the
                     -d option. If it is given, the display strings are listed
                     one per line, not arrayed in columns.

              -J name
                     Gives  the  name of the group of matches the words should
                     be stored in.

              -V name
                     Like -J but naming a unsorted group. These are in a  dif-
                     ferent name space than groups created with the -J flag.

              -1     If given together with the -V option, makes only consecu-
                     tive duplicates in the group be removed. If combined with
                     the  -J  option,  this  has  no visible effect. 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.

              -X explanation
                     The  explanation  string will be printed with the list of
                     matches, above the group currently selected.

              -x message
                     Like -X, but the message will be printed  even  if  there
                     are no matches in the group.

              -q     The suffix given with -S will be automatically 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.

              -r remove-chars
                     This is a more versatile form of the -q option.  The suf-
                     fix  given with -S or the slash automatically added after
                     completing directories will be automatically  removed  if
                     the  next  character  typed inserts one of the characters
                     given in the remove-chars.  This string is  parsed  as  a
                     characters  class and understands the backslash sequences
                     used by the print command.   For  example,  ‘-r  "a-z\t"’
                     removes  the suffix if the next character typed inserts a
                     lowercase character or a TAB, and ‘-r "^0-9"’ removes the
                     suffix if the next character typed inserts anything but a
                     digit. One extra backslash sequence is understood in this
                     string:  ‘\-’ stands for all characters that insert noth-
                     ing. Thus ‘-S "=" -q’ is  the  same  as  ‘-S  "="  -r  "=
                     \t\n\-"’.

                     This  option may also be used without the -S option; then
                     any automatically added space will be removed when one of
                     the characters in the list is typed.

              -R remove-func
                     This  is another form of the -r option. When a suffix has
                     been inserted and the completion accepted,  the  function
                     remove-func  will  be  called  after  the  next character
                     typed.  It is passed the  length  of  the  suffix  as  an
                     argument  and can use the special parameters available in
                     ordinary (non-completion) zle widgets (see zshzle(1))  to
                     analyse and modify the command line.

              -f     If  this  flag  is  given,  all of the matches built from
                     words are marked as being the names of files.   They  are
                     not required to be actual filenames, but if they are, and
                     the option LIST_TYPES is set, the  characters  describing
                     the  types  of  the files in the completion lists will be
                     shown. This also forces a slash to be added when the name
                     of a directory is completed.

              -e     This  flag  can  be used to tell the completion code that
                     the matches added are parameter  names  for  a  parameter
                     expansion.   This  will  make  the  AUTO_PARAM_SLASH  and
                     AUTO_PARAM_KEYS options be used for the matches.

              -W file-prefix
                     This string is a pathname that will be prepended to  each
                     of  the  matches  formed by the given words together with
                     any prefix specified by the -p option to form a  complete
                     filename  for  testing.   Hence it is only useful if com-
                     bined with the -f flag, as the tests will  not  otherwise
                     be performed.

              -F array
                     Specifies  an  array  containing patterns. Words matching
                     one of these patterns are ignored, i.e. not considered to
                     be possible matches.

                     The array may be the name of an array parameter or a list
                     of literal patterns enclosed in parentheses  and  quoted,
                     as  in  ‘-F  "(*?.o  *?.h)"’.  If the name of an array is
                     given, the elements of the array are taken  as  the  pat-
                     terns.

              -Q     This  flag instructs the completion code not to quote any
                     metacharacters in the words when inserting them into  the
                     command line.

              -M match-spec
                     This  gives local match specifications as described below
                     in the section ‘Matching Control’.  This  option  may  be
                     given  more than once. In this case all match-specs given
                     are concatenated with spaces between  them  to  form  the
                     specification string to use.  Note that they will only be
                     used if the -U option is not given.

              -n     Specifies that the words added are to be used as possible
                     matches, but are not to appear in the completion listing.

              -U     If this flag is given, all words given will  be  accepted
                     and no matching will be done by the completion code. Nor-
                     mally this is used in  functions  that  do  the  matching
                     themselves.

              -O array
                     If  this  option is given, the words are not added to the
                     set of possible completions.  Instead, matching  is  done
                     as  usual  and  all  of the words given as arguments that
                     match the string on the command line will  be  stored  in
                     the array parameter whose name is given as array.

              -A array
                     As  the  -O  option,  except that instead of those of the
                     words which match being stored in array, the strings gen-
                     erated  internally by the completion code are stored. For
                     example, with a matching specification of ‘-M  "L:|no="’,
                     the string ‘nof’ on the command line and the string ‘foo’
                     as one of  the  words,  this  option  stores  the  string
                     ‘nofoo’  in  the  array, whereas the -O option stores the
                     ‘foo’ originally given.

              -D array
                     As with -O, the words are not added to the set of  possi-
                     ble  completions.   Instead,  the  completion  code tests
                     whether each word in turn matches what is  on  the  line.
                     If  the n’th word does not match, the n’th element of the
                     array is removed.  Elements for which  the  corresponding
                     word is matched are retained.

              -C     This  option  adds  a  special match which expands to all
                     other matches when inserted into  the  line,  even  those
                     that  are added after this option is used.  Together with
                     the -d option it is possible to  specify  a  string  that
                     should  be  displayed in the list for this special match.
                     If no string is given, it will be shown as a string  con-
                     taining  the strings that would be inserted for the other
                     matches, truncated to the width of the screen.

              -E     This option adds number empty  matches  after  the  words
                     have  been  added.  An empty match takes up space in com-
                     pletion listings but will never be inserted in  the  line
                     and can’t be selected with menu completion or menu selec-
                     tion.  This makes empty matches  only  useful  to  format
                     completion  lists and to make explanatory string be shown
                     in completion lists (since empty  matches  can  be  given
                     display strings with the -d option).  And because all but
                     one empty string would otherwise be removed, this  option
                     implies  the  -V  and  -2 options (even if an explicit -J
                     option is given).

              -
              --     This flag ends the list of flags and options.  All  argu-
                     ments  after  it  will  be  taken  as the words to use as
                     matches even if they begin with hyphens.

              Except for the -M flag, if any of these flags is given more than
              once, the first one (and its argument) will be used.

       compset -p number
       compset -P [ number ] pattern
       compset -s number
       compset -S [ number ] pattern
       compset -n begin [ end ]
       compset -N beg-pat [ end-pat ]
       compset -q
              This  command simplifies modification of the special parameters,
              while its return value allows tests on them to be carried out.

              The options are:

              -p number
                     If the contents of the PREFIX parameter  is  longer  than
                     number   characters,  the  first  number  characters  are
                     removed from it and  appended  to  the  contents  of  the
                     IPREFIX parameter.

              -P [ number ] pattern
                     If the value of the PREFIX parameter begins with anything
                     that matches the pattern, the matched portion is  removed
                     from PREFIX and appended to IPREFIX.

                     Without  the optional number, the longest match is taken,
                     but if number is given,  anything  up  to  the  number’th
                     match is moved.  If the number is negative, the number’th
                     longest match is moved. For example, if  PREFIX  contains
                     the  string  ‘a=b=c’, then compset -P *\= will move the
                     string ‘a=b=’ into the IPREFIX parameter, but compset  -P
                     1 *\= will move only the string ‘a=’.

              -s number
                     As  -p,  but transfer the last number characters from the
                     value of SUFFIX to the front of the value of ISUFFIX.

              -S [ number ] pattern
                     As -P, but match the last portion of SUFFIX and  transfer
                     the matched portion to the front of the value of ISUFFIX.

              -n begin [ end ]
                     If the current word position as specified by the  parame-
                     ter  CURRENT  is greater than or equal to begin, anything
                     up to the begin’th word is removed from the  words  array
                     and  the value of the parameter CURRENT is decremented by
                     begin.

                     If the optional end is given, the  modification  is  done
                     only  if  the  current word position is also less than or
                     equal to end. In this case, the words from  position  end
                     onwards are also removed from the words array.

                     Both  begin  and  end  may be negative to count backwards
                     from the last element of the words array.

              -N beg-pat [ end-pat ]
                     If one of the elements of the words array before the  one
                     at  the index given by the value of the parameter CURRENT
                     matches the pattern  beg-pat,  all  elements  up  to  and
                     including  the  matching  one  are removed from the words
                     array and the value of CURRENT is changed to point to the
                     same word in the changed array.

                     If  the optional pattern end-pat is also given, and there
                     is an element in the words array matching  this  pattern,
                     the  parameters  are  modified  only if the index of this
                     word is higher than the one given by the CURRENT  parame-
                     ter  (so  that the matching word has to be after the cur-
                     sor). In this case,  the  words  starting  with  the  one
                     matching  end-pat  are also removed from the words array.
                     If words contains no word matching end-pat,  the  testing
                     and modification is performed as if it were not given.

              -q     The  word  currently  being  completed is split on spaces
                     into separate words, respecting the usual  shell  quoting
                     conventions.  The resulting words are stored in the words
                     array, and CURRENT, PREFIX, SUFFIX, QIPREFIX, and  QISUF-
                     FIX  are  modified  to reflect the word part that is com-
                     pleted.

              In all the above cases the return value is zero if the test suc-
              ceeded  and the parameters were modified and non-zero otherwise.
              This allows one to use this builtin in tests such as:

                     if compset -P *\=; then ...

              This forces anything up to and including the last equal sign  to
              be ignored by the completion code.

       compcall [ -TD ]
              This  allows  the  use  of  completions defined with the compctl
              builtin from within completion widgets.   The  list  of  matches
              will  be  generated as if one of the non-widget completion func-
              tion (complete-word, etc.)  had been called,  except  that  only
              compctls given for specific commands are used. To force the code
              to try completions defined with the -T option of compctl  and/or
              the  default  completion  (whether  defined by compctl -D or the
              builtin default) in the appropriate places,  the  -T  and/or  -D
              flags can be passed to compcall.

              The return value can be used to test if a matching compctl defi-
              nition was found. It is non-zero if a compctl was found and zero
              otherwise.

              Note that this builtin is defined by the zsh/compctl module.



CONDITION CODES

       The  following  additional condition codes for use within the [[ ... ]]
       construct are available in completion widgets.  These work on the  spe-
       cial  parameters.   All  of  these  tests  can also be performed by the
       compset builtin, but in the case of the condition codes the contents of
       the special parameters are not modified.

       -prefix [ number ] pattern
              true if the test for the -P option of compset would succeed.

       -suffix [ number ] pattern
              true if the test for the -S option of compset would succeed.

       -after beg-pat
              true  if  the  test of the -N option with only the beg-pat given
              would succeed.

       -between beg-pat end-pat
              true if the test for the -N option with both patterns would suc-
              ceed.



MATCHING CONTROL

       It  is  possible by use of the -M option of the compadd builtin command
       to specify how the characters in the string to be  completed  (referred
       to  here  as  the  command line) map onto the characters in the list of
       matches produced by the completion code (referred to here as the  trial
       completions). Note that this is not used if the command line contains a
       glob pattern and the GLOB_COMPLETE option is set or  the  pattern_match
       of the compstate special association is set to a non-empty string.

       The  match-spec  given  as  the argument to the -M option (see ‘Builtin
       Commands’ above) consists of one or more  matching  descriptions  sepa-
       rated by whitespace.  Each description consists of a letter followed by
       a colon and then the patterns describing which character  sequences  on
       the  line match which character sequences in the trial completion.  Any
       sequence of characters not handled in this fashion must match  exactly,
       as usual.

       The  forms  of  match-spec understood are as follows. In each case, the
       form with an uppercase initial character  retains  the  string  already
       typed on the command line as the final result of completion, while with
       a lowercase initial character the string on the command line is changed
       into the corresponding part of the trial completion.

       m:lpat=tpat
       M:lpat=tpat
              Here, lpat is a pattern that matches on the command line, corre-
              sponding to tpat which matches in the trial completion.

       l:lanchor|lpat=tpat
       L:lanchor|lpat=tpat
       l:lanchor||ranchor=tpat
       L:lanchor||ranchor=tpat
       b:lpat=tpat
       B:lpat=tpat
              These letters are for patterns that are anchored by another pat-
              tern  on  the  left side. Matching for lpat and tpat is as for m
              and M, but the pattern lpat matched on the command line must  be
              preceded  by  the  pattern lanchor.  The lanchor can be blank to
              anchor the match to the start of the command line string; other-
              wise  the  anchor can occur anywhere, but must match in both the
              command line and trial completion strings.

              If no lpat is given but a  ranchor  is,  this  matches  the  gap
              between  substrings  matched by lanchor and ranchor. Unlike lan-
              chor, the ranchor only  needs  to  match  the  trial  completion
              string.

              The  b  and B forms are similar to l and L with an empty anchor,
              but need to match only the beginning of the trial completion  or
              the word on the command line, respectively.

       r:lpat|ranchor=tpat
       R:lpat|ranchor=tpat
       r:lanchor||ranchor=tpat
       R:lanchor||ranchor=tpat
       e:lpat=tpat
       E:lpat=tpat
              As  l, L, b and B, with the difference that the command line and
              trial completion patterns are anchored on the right side.   Here
              an  empty  ranchor  and the e and E forms force the match to the
              end of the trial completion or command line string.

       Each lpat, tpat or anchor is either an empty string or  consists  of  a
       sequence  of literal characters (which may be quoted with a backslash),
       question marks, character classes, and correspondence classes; ordinary
       shell patterns are not used.  Literal characters match only themselves,
       question marks match any character, and character classes are formed as
       for globbing and match any character in the given set.

       Correspondence classes are defined like character classes, but with two
       differences: they are delimited  by  a  pair  of  braces,  and  negated
       classes  are  not  allowed,  so  the characters ! and ^ have no special
       meaning directly after the opening brace.  They indicate that  a  range
       of characters on the line match a range of characters in the trial com-
       pletion, but (unlike ordinary character classes)  paired  according  to
       the  corresponding  position  in the sequence. For example, to make any
       lowercase letter on the line match the corresponding  uppercase  letter
       in  the  trial  completion, you can use ‘m:{a-z}={A-Z}’.  More than one
       pair of classes can occur, in which case the first class before  the  =
       corresponds  to  the  first  after it, and so on.  If one side has more
       such classes than the other side, the superfluous classes  behave  like
       normal  character  classes.   In anchor patterns correspondence classes
       also behave like normal character classes.

       The pattern tpat may also be one or two stars, ‘*’ or ‘**’. This  means
       that the pattern on the command line can match any number of characters
       in the trial completion. In this case the pattern must be anchored  (on
       either  side); in the case of a single star, the anchor then determines
       how much of the trial completion is to be included --- only the charac-
       ters  up to the next appearance of the anchor will be matched. With two
       stars, substrings matched by the anchor can be matched, too.

       Examples:

       The keys of the options association defined by the parameter module are
       the  option names in all-lowercase form, without underscores, and with-
       out the optional no at the beginning even though  the  builtins  setopt
       and  unsetopt  understand  option  names with uppercase letters, under-
       scores, and the optional no.  The following alters the  matching  rules
       so  that  the  prefix  no and any underscore are ignored when trying to
       match the trial completions generated and uppercase letters on the line
       match the corresponding lowercase letters in the words:

              compadd -M L:|[nN][oO]= M:_= M:{A-Z}={a-z} - \
                ${(k)options}

       The  first  part says that the pattern ‘[nN][oO]’ at the beginning (the
       empty anchor before the pipe symbol) of the string on the line  matches
       the  empty  string  in the list of words generated by completion, so it
       will be ignored if present. The second part does the same for an under-
       score anywhere in the command line string, and the third part uses cor-
       respondence classes so that any uppercase letter on  the  line  matches
       the  corresponding  lowercase letter in the word. The use of the upper-
       case forms of the specification characters (L and  M)  guarantees  that
       what has already been typed on the command line (in particular the pre-
       fix no) will not be deleted.

       Note that the use of L in the first part means  that  it  matches  only
       when  at  the  beginning  of both the command line string and the trial
       completion.  I.e.,  the  string  ‘_NO_f’  would  not  be  completed  to
       ‘_NO_foo’, nor would ‘NONO_f’ be completed to ‘NONO_foo’ because of the
       leading underscore or the second ‘NO’ on the line which makes the  pat-
       tern  fail  even  though  they  are otherwise ignored. To fix this, one
       would use ‘B:[nN][oO]=’ instead of the first part. As described  above,
       this  matches  at the beginning of the trial completion, independent of
       other characters or substrings at the beginning  of  the  command  line
       word which are ignored by the same or other match-specs.

       The second example makes completion case insensitive.  This is just the
       same as in the option example, except here we wish to retain the  char-
       acters in the list of completions:

              compadd -M m:{a-z}={A-Z} ...

       This  makes  lowercase  letters match their uppercase counterparts.  To
       make uppercase letters match the lowercase forms as well:

              compadd -M m:{a-zA-Z}={A-Za-z} ...

       A nice example for the use of * patterns is  partial  word  completion.
       Sometimes  you  would  like  to  make  strings like ‘c.s.u’ complete to
       strings like ‘comp.source.unix’, i.e. the word on the command line con-
       sists of multiple parts, separated by a dot in this example, where each
       part should be completed separately --- note, however,  that  the  case
       where  each  part of the word, i.e. ‘comp’, ‘source’ and ‘unix’ in this
       example, is to be completed from separate sets of matches is a  differ-
       ent  problem  to be solved by the implementation of the completion wid-
       get.  The example can be handled by:

              compadd -M r:|.=* r:|=* \
                - comp.sources.unix comp.sources.misc ...

       The first specification says that  lpat  is  the  empty  string,  while
       anchor  is  a dot; tpat is *, so this can match anything except for the
       ‘.’ from the anchor in the trial completion word.  So in  ‘c.s.u’,  the
       matcher  sees ‘c’, followed by the empty string, followed by the anchor
       ‘.’, and likewise for the second dot, and replaces  the  empty  strings
       before  the  anchors,  giving ‘c[omp].s[ources].u[nix]’, where the last
       part of the completion is just as normal.

       With the pattern shown above, the string ‘c.u’ could not  be  completed
       to  ‘comp.sources.unix’  because  the  single  star  means  that no dot
       (matched by the anchor) can be  skipped.  By  using  two  stars  as  in
       ‘r:|.=**’,  however,  ‘c.u’  could be completed to ‘comp.sources.unix’.
       This also shows that in some cases, especially if the anchor is a  real
       pattern,  like a character class, the form with two stars may result in
       more matches than one would like.

       The second specification is needed to make this work when the cursor is
       in  the  middle  of  the string on the command line and the option COM-
       PLETE_IN_WORD is set. In this case the completion code  would  normally
       try  to  match  trial  completions that end with the string as typed so
       far, i.e. it will only insert new characters  at  the  cursor  position
       rather  then at the end.  However in our example we would like the code
       to recognise matches which contain extra characters after the string on
       the  line  (the  ‘nix’  in  the  example).  Hence we say that the empty
       string at the end of the string on the line matches any  characters  at
       the end of the trial completion.

       More generally, the specification

              compadd -M r:|[.,_-]=* r:|=* ...

       allows one to complete words with abbreviations before any of the char-
       acters in the square brackets.  For example, to complete  veryverylong-
       file.c  rather  than veryverylongheader.h with the above in effect, you
       can just type very.c before attempting completion.

       The specifications with both a left and a right anchor  are  useful  to
       complete  partial  words  whose parts are not separated by some special
       character. For example, in some places strings  have  to  be  completed
       that are formed ‘LikeThis’ (i.e. the separate parts are determined by a
       leading uppercase letter) or maybe one has  to  complete  strings  with
       trailing  numbers.  Here  one  could  use the simple form with only one
       anchor as in:

              compadd -M r:|[A-Z0-9]=* r:|=* LikeTHIS FooHoo 5foo123 5bar234

       But with this, the string ‘H’ would neither complete to ‘FooHoo’ nor to
       ‘LikeTHIS’ because in each case there is an uppercase letter before the
       ‘H’ and that is matched by the anchor. Likewise, a  ‘2’  would  not  be
       completed.   In   both   cases   this   could   be   changed  by  using
       ‘r:|[A-Z0-9]=**’,  but  then  ‘H’  completes  to  both  ‘LikeTHIS’  and
       ‘FooHoo’  and a ‘2’ matches the other strings because characters can be
       inserted before every uppercase letter and digit.  To  avoid  this  one
       would use:

              compadd -M r:[^A-Z0-9]||[A-Z0-9]=** r:|=* \
                  LikeTHIS FooHoo foo123 bar234

       By  using these two anchors, a ‘H’ matches only uppercase ‘H’s that are
       immediately preceded by something matching the left anchor ‘[^A-Z0-9]’.
       The  effect is, of course, that ‘H’ matches only the string ‘FooHoo’, a
       ‘2’ matches only ‘bar234’ and so on.

       When using the completion system (see zshcompsys(1)), users can  define
       match specifications that are to be used for specific contexts by using
       the matcher and matcher-list styles. The values for the latter will  be
       used everywhere.



COMPLETION WIDGET EXAMPLE

       The first step is to define the widget:

              zle -C complete complete-word complete-files

       Then  the  widget  can be bound to a key using the bindkey builtin com-
       mand:

              bindkey ^X\t complete

       After that the shell function complete-files will be invoked after typ-
       ing  control-X  and TAB. The function should then generate the matches,
       e.g.:

              complete-files () { compadd - * }

       This function will complete files in the current directory matching the
       current word.



zsh 4.2.1                       August 13, 2004                  ZSHCOMPWID(1)

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