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


This document describes version 0.011 of AppBase::Grep (from Perl distribution AppBase-Grep), released on 2023-07-22.




 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, 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.

  • 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)



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


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


Please visit the project's homepage at


Source repository is at


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.


perlancar <>


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.


This software is copyright (c) 2023, 2022, 2021, 2020, 2018 by perlancar <>.

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


Please report any bugs or feature requests on the bugtracker website

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.