sort::versions(3pm) [debian man page]
Versions(3pm) User Contributed Perl Documentation Versions(3pm) NAME
Sort::Versions - a perl 5 module for sorting of revision-like numbers SYNOPSIS
use Sort::Versions; @l = sort { versioncmp($a, $b) } qw( 1.2 1.2.0 1.2a.0 1.2.a 1.a 02.a ); ... use Sort::Versions; print 'lower' if versioncmp('1.2', '1.2a') == -1; ... use Sort::Versions; %h = (1 => 'd', 2 => 'c', 3 => 'b', 4 => 'a'); @h = sort { versioncmp($h{$a}, $h{$b}) } keys %h; DESCRIPTION
Sort::Versions allows easy sorting of mixed non-numeric and numeric strings, like the 'version numbers' that many shared library systems and revision control packages use. This is quite useful if you are trying to deal with shared libraries. It can also be applied to applications that intersperse variable-width numeric fields within text. Other applications can undoubtedly be found. For an explanation of the algorithm, it's simplest to look at these examples: 1.1 < 1.2 1.1a < 1.2 1.1 < 1.1.1 1.1 < 1.1a 1.1.a < 1.1a 1 < a a < b 1 < 2 1.1-3 < 1.1-4 1.1-5 < 1.1.6 More precisely (but less comprehensibly), the two strings are treated as subunits delimited by periods or hyphens. Each subunit can contain any number of groups of digits or non-digits. If digit groups are being compared on both sides, a numeric comparison is used, otherwise a ASCII ordering is used. A group or subgroup with more units will win if all comparisons are equal. A period binds digit groups together more tightly than a hyphen. Some packages use a different style of version numbering: a simple real number written as a decimal. Sort::Versions has limited support for this style: when comparing two subunits which are both digit groups, if either subunit has a leading zero, then both are treated like digits after a decimal point. So for example: 0002 < 1 1.06 < 1.5 This won't always work, because there won't always be a leading zero in real-number style version numbers. There is no way for Sort::Versions to know which style was intended. But a lot of the time it will do the right thing. If you are making up version numbers, the style with (possibly) more than one dot is the style to use. USAGE
The function "versioncmp()" takes two arguments and compares them like "cmp". With perl 5.6 or later, you can also use this function directly in sorting: @l = sort versioncmp qw(1.1 1.2 1.0.3); The function "versions()" can be used directly as a sort function even on perl 5.005 and earlier, but its use is deprecated. AUTHOR
Ed Avis <ed@membled.com> and Matt Johnson <mwj99@doc.ic.ac.uk> for recent releases; the original author is Kenneth J. Albanowski <kjahds@kjahds.com>. Thanks to Hack Kampbjorn and Slaven Rezic for patches and bug reports. Copyright (c) 1996, Kenneth J. Albanowski. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.10.0 2003-08-24 Versions(3pm)
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Module::Versions::Report(3pm) User Contributed Perl Documentation Module::Versions::Report(3pm) NAME
Module::Versions::Report -- report versions of all modules in memory SYNOPSIS
use Module::Versions::Report; ...and any code you want... This will run all your code normally, but then as the Perl interpreter is about to exit, it will print something like: Perl v5.6.1 under MSWin32. Modules in memory: attributes; AutoLoader v5.58; Carp; Config; DynaLoader v1.04; Exporter v5.562; Module::Versions::Report v1.01; HTML::Entities v1.22; HTML::HeadParser v2.15; HTML::Parser v3.25; [... and whatever other modules were loaded that session...] Consider its use from the command line: % perl -MModule::Versions::Report -MLWP -e 1 Perl v5.6.1 under MSWin32. Modules in memory: attributes; AutoLoader v5.58; [...] DESCRIPTION
I often get email from someone reporting a bug in a module I've written. I email back, asking what version of the module it is, what version of Perl on what OS, and sometimes what version of some relevent third library (like XML::Parser). They reply, saying "Perl 5". I say "I need the exact version, as reported by "perl -v"". They tell me. And I say "I, uh, also asked about the version of my module and XML::Parser [or whatever]". They say "Oh yeah. It's 2.27". "Is that my module or XML::Parser?" "XML::Parser." "OK, and what about my module's version?" "Ohyeah. That's 3.11." By this time, days have passed, and what should have been a simple operation -- reporting the version of Perl and relevent modules, has been needlessly complicated. This module is for simplifying that task. If you add "use Module::Versions::Report;" to a program (especially handy if your program is one that demonstrates a bug in some module), then when the program has finished running, you well get a report detailing the all modules in memory, and noting the version of each (for modules that defined a $VERSION, at least). USING
Importing If this package is imported then END block is set, and report printed to stdout on a program exit, so use "use Module::Versions::Report;" if you need a report on exit or "use Module::Versions::Report ();" otherwise and call report or print_report functions yourself. report and print_report functions The first one returns preformatted report as a string, the latter outputs a report to stdout. COPYRIGHT AND DISCLAIMER
Copyright 2001-2003 Sean M. Burke. This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose. MAINTAINER
Ruslan U. Zakirov <ruz@bestpractical.com> AUTHOR
Sean M. Burke, <sburke@cpan.org> perl v5.10.0 2008-10-21 Module::Versions::Report(3pm)