NAME
    AppBase::Grep - A base for grep-like CLI utilities

VERSION
    This document describes version 0.012 of AppBase::Grep (from Perl
    distribution AppBase-Grep), released on 2024-01-25.

FUNCTIONS
  grep
    Usage:

     grep(%args) -> [$status_code, $reason, $payload, \%result_meta]

    A base for grep-like CLI utilities.

    This routine provides a base for grep-like CLI utilities. It accepts
    coderef as source of lines, which in the actual utilities can be from
    files or other sources. It provides common options like "-i", "-v",
    "-c", color highlighting, and so on.

    Examples of CLI utilities that are based on this: abgrep, grep-coin
    (from App::CryptoCurrencyUtils).

    Why? For grepping lines from files or stdin, abgrep is no match for the
    standard grep (or its many alternatives): it's orders of magnitude
    slower and currently has fewer options. But AppBase::Grep is a quick way
    to create grep-like utilities that grep from a custom sources but have
    common/standard grep features.

    Compared to the standard grep, AppBase::Grep also has these unique
    features:

    *   "--all" option to match all patterns instead of just one;

    *   observe the "COLOR" environment variable to set "--color" default;

    This function is not exported.

    Arguments ('*' denotes required arguments):

    *   all => *true*

        Require all patterns to match, instead of just one.

    *   color => *str* (default: "auto")

        Specify when to show color (never, always, or auto/when
        interactive).

    *   count => *true*

        Supress normal output; instead return a count of matching lines.

    *   dash_prefix_inverts => *bool*

        When given pattern that starts with dash "-FOO", make it to mean
        "^(?!.*FOO)".

        This is a convenient way to search for lines that do not match a
        pattern. Instead of using "-v" to invert the meaning of all
        patterns, this option allows you to invert individual pattern using
        the dash prefix, which is also used by Google search and a few other
        search engines.

    *   files_with_matches => *true*

        Supress normal output; instead return filenames with matching lines;
        scanning for each file will stop on the first match.

    *   files_without_match => *true*

        Supress normal output; instead return filenames without matching
        lines.

    *   ignore_case => *bool*

        If set to true, will search case-insensitively.

    *   invert_match => *bool*

        Invert the sense of matching.

    *   line_number => *true*

        Show line number along with matches.

    *   pattern => *str*

        Specify *string* to search for.

    *   quiet => *true*

        Do not print matches, only return appropriate exit code.

    *   regexps => *array[str]*

        Specify additional *regexp pattern* to search for.

    Returns an enveloped result (an array).

    First element ($status_code) is an integer containing HTTP-like status
    code (200 means OK, 4xx caller error, 5xx function error). Second
    element ($reason) is a string containing error message, or something
    like "OK" if status is 200. Third element ($payload) is the actual
    result, but usually not present when enveloped result is an error
    response ($status_code is not 2xx). Fourth element (%result_meta) is
    called result metadata and is optional, a hash that contains extra
    information, much like how HTTP response headers provide additional
    metadata.

    Return value: (any)

ENVIRONMENT
  NO_COLOR
    If set, will disable color. Takes precedence over "COLOR" but not
    "--color".

  COLOR
    Boolean. If set to true, will set default "--color" to "always" instead
    of "auto". If set to false, will set default "--color" to "never"
    instead of "auto". This behavior is not in GNU grep.

  COLOR_THEME
    String. Will search color themes in "AppBase::Grep::ColorTheme::*" as
    well as "Generic::ColorTheme::*" modules.

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

SOURCE
    Source repository is at
    <https://github.com/perlancar/perl-AppBase-Grep>.

SEE ALSO
    Some scripts that use us as a base: abgrep (from App::abgrep),
    grep-email (from App::grep::email), grep-url (from App::grep::url),
    pdfgrep (a.k.a. grep-from-pdf, from App::PDFUtils).

    Regexp::From::String is related to "--dash-prefix-inverts" option.

AUTHOR
    perlancar <perlancar@cpan.org>

CONTRIBUTING
    To contribute, you can send patches by email/via RT, or send pull
    requests on GitHub.

    Most of the time, you don't need to build the distribution yourself. You
    can simply modify the code, then test via:

     % prove -l

    If you want to build the distribution (e.g. to try to install it locally
    on your system), you can install Dist::Zilla,
    Dist::Zilla::PluginBundle::Author::PERLANCAR,
    Pod::Weaver::PluginBundle::Author::PERLANCAR, and sometimes one or two
    other Dist::Zilla- and/or Pod::Weaver plugins. Any additional steps
    required beyond that are considered a bug and can be reported to me.

COPYRIGHT AND LICENSE
    This software is copyright (c) 2024, 2023, 2022, 2021, 2020, 2018 by
    perlancar <perlancar@cpan.org>.

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

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

    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.