Acme-CPANModules-ReadingFilesBackward

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package Acme::CPANModules::ReadingFilesBackward;

use strict;

use Acme::CPANModulesUtil::Misc;

our $AUTHORITY = 'cpan:PERLANCAR'; # AUTHORITY
our $DATE = '2023-10-31'; # DATE
our $DIST = 'Acme-CPANModules-ReadingFilesBackward'; # DIST
our $VERSION = '0.003'; # VERSION

our $LIST = {
    summary => 'List of modules to read files backward (in reverse)',
    description => <<'_',

Probably the fastest way, if you are on a Unix system, is to use the **tac**
command, which can read a file line by line in reverse order, or paragraph by
paragraph, or character by character, or word by word, or by a custom separator
string or regular expression. Example for using it from Perl:

    open my $fh, "tac /etc/passwd |";
    print while <$fh>;

Another convenient way is to use the Perl I/O layer <pm:PerlIO::reverse>. It
only does line-by-line reversing, but you can use the regular Perl API. You
don't even have to `use` the module explicitly (but of course you have to get it
installed first):

    open my $fh, "<:reverse", "/etc/passwd";
    print while <$fh>;

If your file is small (fits in your system's memory), you can also slurp the
file contents first into an array (either line by line, or paragraph by
paragraph, or what have you) and then simply `reverse` the array:

    open my $fh, "<", "/etc/passwd";
    my @lines = <$fh>;
    print for reverse @lines;

If the above solutions do not fit your needs, there are also these modules which
can help: <pm:File::ReadBackward>, <pm:File::Bidirectional>. File::ReadBackward
is slightly faster than File::Bidirectional, but File::Bidirectional can read
forward as well as backward. I now simply prefer PerlIO::reverse because I don't
have to use a custom API for reading files.

_
    'x.app.cpanmodules.show_entries' => 0,
};

Acme::CPANModulesUtil::Misc::populate_entries_from_module_links_in_description;

1;
# ABSTRACT: List of modules to read files backward (in reverse)

__END__

=pod

=encoding UTF-8

=head1 NAME

Acme::CPANModules::ReadingFilesBackward - List of modules to read files backward (in reverse)

=head1 VERSION

This document describes version 0.003 of Acme::CPANModules::ReadingFilesBackward (from Perl distribution Acme-CPANModules-ReadingFilesBackward), released on 2023-10-31.

=head1 DESCRIPTION

Probably the fastest way, if you are on a Unix system, is to use the B<tac>
command, which can read a file line by line in reverse order, or paragraph by
paragraph, or character by character, or word by word, or by a custom separator
string or regular expression. Example for using it from Perl:

 open my $fh, "tac /etc/passwd |";
 print while <$fh>;

Another convenient way is to use the Perl I/O layer L<PerlIO::reverse>. It
only does line-by-line reversing, but you can use the regular Perl API. You
don't even have to C<use> the module explicitly (but of course you have to get it
installed first):

 open my $fh, "<:reverse", "/etc/passwd";
 print while <$fh>;

If your file is small (fits in your system's memory), you can also slurp the
file contents first into an array (either line by line, or paragraph by
paragraph, or what have you) and then simply C<reverse> the array:

 open my $fh, "<", "/etc/passwd";
 my @lines = <$fh>;
 print for reverse @lines;

If the above solutions do not fit your needs, there are also these modules which
can help: L<File::ReadBackward>, L<File::Bidirectional>. File::ReadBackward
is slightly faster than File::Bidirectional, but File::Bidirectional can read
forward as well as backward. I now simply prefer PerlIO::reverse because I don't
have to use a custom API for reading files.

=head1 ACME::CPANMODULES ENTRIES

=over

=item L<PerlIO::reverse>

Author: L<GFUJI|https://metacpan.org/author/GFUJI>

=item L<File::ReadBackward>

=item L<File::Bidirectional>

Author: L<KIANWIN|https://metacpan.org/author/KIANWIN>

=back

=head1 FAQ

=head2 What is an Acme::CPANModules::* module?

An Acme::CPANModules::* module, like this module, contains just a list of module
names that share a common characteristics. It is a way to categorize modules and
document CPAN. See L<Acme::CPANModules> for more details.

=head2 What are ways to use this Acme::CPANModules module?

Aside from reading this Acme::CPANModules module's POD documentation, you can
install all the listed modules (entries) using L<cpanm-cpanmodules> script (from
L<App::cpanm::cpanmodules> distribution):

 % cpanm-cpanmodules -n ReadingFilesBackward

Alternatively you can use the L<cpanmodules> CLI (from L<App::cpanmodules>
distribution):

    % cpanmodules ls-entries ReadingFilesBackward | cpanm -n

or L<Acme::CM::Get>:

    % perl -MAcme::CM::Get=ReadingFilesBackward -E'say $_->{module} for @{ $LIST->{entries} }' | cpanm -n

or directly:

    % perl -MAcme::CPANModules::ReadingFilesBackward -E'say $_->{module} for @{ $Acme::CPANModules::ReadingFilesBackward::LIST->{entries} }' | cpanm -n

This Acme::CPANModules module also helps L<lcpan> produce a more meaningful
result for C<lcpan related-mods> command when it comes to finding related
modules for the modules listed in this Acme::CPANModules module.
See L<App::lcpan::Cmd::related_mods> for more details on how "related modules"
are found.

=head1 HOMEPAGE

Please visit the project's homepage at L<https://metacpan.org/release/Acme-CPANModules-ReadingFilesBackward>.

=head1 SOURCE

Source repository is at L<https://github.com/perlancar/perl-Acme-CPANModules-ReadingFilesBackward>.

=head1 SEE ALSO

L<Acme::CPANModules::PickingRandomLinesFromFile>

L<Acme::CPANModules> - about the Acme::CPANModules namespace

L<cpanmodules> - CLI tool to let you browse/view the lists

=head1 AUTHOR

perlancar <perlancar@cpan.org>

=head1 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 L<Dist::Zilla>,
L<Dist::Zilla::PluginBundle::Author::PERLANCAR>,
L<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.

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2023, 2020, 2019 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.

=head1 BUGS

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

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.

=cut



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