NAME
Acme::CPANModules::ReadingFilesBackward - List of modules to read files backward (in reverse)
VERSION
This document describes version 0.003 of Acme::CPANModules::ReadingFilesBackward (from Perl distribution Acme-CPANModules-ReadingFilesBackward), released on 2023-10-31.
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 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: File::ReadBackward, 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.
ACME::CPANMODULES ENTRIES
- PerlIO::reverse
-
Author: GFUJI
- File::ReadBackward
- File::Bidirectional
-
Author: KIANWIN
FAQ
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 Acme::CPANModules for more details.
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 cpanm-cpanmodules script (from App::cpanm::cpanmodules distribution):
% cpanm-cpanmodules -n ReadingFilesBackward
Alternatively you can use the cpanmodules CLI (from App::cpanmodules distribution):
% cpanmodules ls-entries ReadingFilesBackward | cpanm -n
or 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 lcpan produce a more meaningful result for lcpan related-mods
command when it comes to finding related modules for the modules listed in this Acme::CPANModules module. See App::lcpan::Cmd::related_mods for more details on how "related modules" are found.
HOMEPAGE
Please visit the project's homepage at https://metacpan.org/release/Acme-CPANModules-ReadingFilesBackward.
SOURCE
Source repository is at https://github.com/perlancar/perl-Acme-CPANModules-ReadingFilesBackward.
SEE ALSO
Acme::CPANModules::PickingRandomLinesFromFile
Acme::CPANModules - about the Acme::CPANModules namespace
cpanmodules - CLI tool to let you browse/view the lists
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) 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.
BUGS
Please report any bugs or feature requests on the bugtracker website 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.