NAME
    Complete::Bash - Completion module for bash shell

VERSION
    This document describes version 0.10 of Complete::Bash (from Perl
    distribution Complete-Bash), released on 2014-07-25.

DESCRIPTION
    Bash allows completion to come from various sources. The simplest is
    from a list of words ("-W"):

     % complete -W "one two three four" somecmd
     % somecmd t<Tab>
     two  three

    Another source is from a bash function ("-F"). The function will receive
    input in two variables: "COMP_WORDS" (array, command-line chopped into
    words) and "COMP_CWORD" (integer, index to the array of words indicating
    the cursor position). It must set an array variable "COMPREPLY" that
    contains the list of possible completion:

     % _foo()
     {
       local cur
       COMPREPLY=()
       cur=${COMP_WORDS[COMP_CWORD]}
       COMPREPLY=($( compgen -W '--help --verbose --version' -- $cur ) )
     }
     % complete -F _foo foo
     % foo <Tab>
     --help  --verbose  --version

    And yet another source is an external command (including, a Perl
    script). The command receives two environment variables: "COMP_LINE"
    (string, raw command-line) and "COMP_POINT" (integer, cursor location).
    Program must split "COMP_LINE" into words, find the word to be
    completed, complete that, and return the list of words one per-line to
    STDOUT. An example:

     % cat foo-complete
     #!/usr/bin/perl
     use Complete::Bash qw(parse_cmdline format_completion);
     use Complete::Util qw(complete_array_elem);
     my ($words, $cword) = parse_cmdline();
     my $res = complete_array_elem(array=>[qw/--help --verbose --version/], word=>$words->[$cword]);
     print format_completion($res);

     % complete -C foo-complete foo
     % foo --v<Tab>
     --verbose --version

    This module provides routines for you to be doing the above.

    Instead of being called by bash as an external command every time user
    presses Tab, you can also use Perl to *generate* bash "complete" scripts
    for you. See Complete::BashGen.

FUNCTIONS
  format_completion($shell_completion) -> array|str
    Format completion for output (for shell).

    Bash accepts completion reply in the form of one entry per line to
    STDOUT. Some characters will need to be escaped. This function helps you
    do the formatting, with some options.

    This function accepts an array (the result of a "complete_*" function),
    *or* a hash (which contains the completion array from a "complete_*"
    function as well as other metadata for formatting hints). Known keys:

    *   "completion" (array): The completion array. You can put the result
        of "complete_*" function here.

    *   "as" (str): Either "string" (the default) or "array" (to return
        array of lines instead of the lines joined together). Returning
        array is useful if you are doing completion inside "Term::ReadLine",
        for example, where the library expects an array.

    *   "escmode" (str): Escaping mode for entries. Either "default" (most
        nonalphanumeric characters will be escaped), "shellvar" (like
        "default", but dollar sign "$" will not be escaped, convenient when
        completing environment variables for example), "filename" (currently
        equals to "default"), "option" (currently equals to "default"), or
        "none" (no escaping will be done).

    *   "path_sep" (str): If set, will enable "path mode", useful for
        completing/drilling-down path. Below is the description of "path
        mode".

        In shell, when completing filename (e.g. "foo") and there is only a
        single possible completion (e.g. "foo" or "foo.txt"), the shell will
        display the completion in the buffer and automatically add a space
        so the user can move to the next argument. This is also true when
        completing other values like variables or program names.

        However, when completing directory (e.g. "/et" or "Downloads") and
        there is solely a single completion possible and it is a directory
        (e.g. "/etc" or "Downloads"), the shell automatically adds the path
        separator character instead ("/etc/" or "Downloads/"). The user can
        press Tab again to complete for files/directories inside that
        directory, and so on. This is obviously more convenient compared to
        when shell adds a space instead.

        The "path_sep" option, when set, will employ a trick to mimic this
        behaviour. The trick is, if you have a completion array of
        "['foo/']", it will be changed to "['foo/', 'foo/ ']" (the second
        element is the first element with added space at the end) to prevent
        bash from adding a space automatically.

        Path mode is not restricted to completing filesystem paths. Anything
        path-like can use it. For example when you are completing Java or
        Perl package name (e.g. "com.company.product.whatever" or
        "File::Spec::Unix") you can use this mode (with "path_sep"
        appropriately set to, e.g. "." or "::"). But note that in the case
        of "::" since colon is a word-breaking character in Bash by default,
        when typing you'll need to escape it (e.g. "mpath File\:\:Sp<tab>")
        or use it inside quotes (e.g. "mpath "File::Sp<tab>").

    Arguments ('*' denotes required arguments):

    *   shell_completion* => *array|hash*

        Result of shell completion.

        Either an array or hash. See function description for more details.

    Return value:

    Formatted string (or array, if `as` is set to `array`) (any)

  parse_cmdline($cmdline, $point, $word_breaks, $preserve_quotes) -> array
    Parse shell command-line for processing by completion routines.

    Currently only supports bash. This function basically converts COMP_LINE
    (str) and COMP_POINT (int) to become COMP_WORDS (array) and COMP_CWORD
    (int), like what bash supplies to shell functions. The differences with
    bash are: 1) quotes and backslashes are by default stripped, unless you
    specify "preserve_quotes"; 2) no word-breaking characters aside from
    whitespaces are used, unless you specify more word-breaking characters
    by setting "word_breaks".

    Arguments ('*' denotes required arguments):

    *   cmdline => *str*

        Command-line, defaults to COMP_LINE environment.

    *   point => *int*

        Point/position to complete in command-line, defaults to COMP_POINT.

    *   preserve_quotes => *bool* (default: 0)

        Whether to preserve quotes, like bash does.

    *   word_breaks => *str*

        Extra characters to break word at.

        In addition to space and tab.

        Example: "=:".

        Note that the characters won't break words if inside quotes or
        escaped.

    Return value:

     (array)

    Return a 2-element array: `[$words, $cword]`. `$words` is array of str,
    equivalent to `COMP_WORDS` provided by bash to shell functions. `$cword`
    is an integer, equivalent to `COMP_CWORD` provided by bash to shell
    functions. The word to be completed is at `$words->[$cword]`.

    Note that COMP_LINE includes the command name. If you want the
    command-line arguments only (like in `@ARGV`), you need to strip the
    first element from `$words` and reduce `$cword` by 1.

TODOS
    format_completion(): Accept regex for path_sep.

SEE ALSO
    Complete

    Complete::BashGen

    Other modules related to bash shell tab completion: Bash::Completion,
    Getopt::Complete. Term::Bash::Completion::Generator

    Programmable Completion section in Bash manual:
    <https://www.gnu.org/software/bash/manual/html_node/Programmable-Complet
    ion.html>

HOMEPAGE
    Please visit the project's homepage at
    <https://metacpan.org/release/Complete-Bash>.

SOURCE
    Source repository is at
    <https://github.com/sharyanto/perl-Complete-Bash>.

BUGS
    Please report any bugs or feature requests on the bugtracker website
    <https://rt.cpan.org/Public/Dist/Display.html?Name=Complete-Bash>

    When submitting a bug or request, please include a test-file or a patch
    to an existing test-file that illustrates the bug or desired feature.

AUTHOR
    Steven Haryanto <stevenharyanto@gmail.com>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2014 by Steven Haryanto.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.

