X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/129318bdc5341dc6c9c199fa27cbfe9b42b96328..32709fdf41543f067562e0dc9944448dd11d2c28:/lib/version.pm diff --git a/lib/version.pm b/lib/version.pm index 15cf81b..9201a02 100644 --- a/lib/version.pm +++ b/lib/version.pm @@ -1,346 +1,56 @@ -#!/usr/bin/perl -w +#!perl -w package version; -use 5.005_03; +use 5.005_04; use strict; -require DynaLoader; -use vars qw(@ISA $VERSION $CLASS); +use vars qw(@ISA $VERSION $CLASS *declare *qv); -@ISA = qw(DynaLoader); - -$VERSION = (qw$Revision: 2.7 $)[1]/10; +$VERSION = 0.77; $CLASS = 'version'; -local $^W; # shut up the 'redefined' warning for UNIVERSAL::VERSION -bootstrap version if $] < 5.009; - # Preloaded methods go here. +sub import { + no strict 'refs'; + my ($class) = shift; + + # Set up any derived class + unless ($class eq 'version') { + local $^W; + *{$class.'::declare'} = \&version::declare; + *{$class.'::qv'} = \&version::qv; + } + + my %args; + if (@_) { # any remaining terms are arguments + map { $args{$_} = 1 } @_ + } + else { # no parameters at all on use line + %args = + ( + qv => 1, + 'UNIVERSAL::VERSION' => 1, + ); + } + + my $callpkg = caller(); + + if (exists($args{declare})) { + *{$callpkg."::declare"} = + sub {return $class->declare(shift) } + unless defined(&{$callpkg.'::declare'}); + } + + if (exists($args{qv})) { + *{$callpkg."::qv"} = + sub {return $class->qv(shift) } + unless defined(&{"$callpkg\::qv"}); + } + + if (exists($args{'VERSION'})) { + *{$callpkg."::VERSION"} = \&version::_VERSION; + } +} 1; -__END__ - -=head1 NAME - -version - Perl extension for Version Objects - -=head1 SYNOPSIS - - use version; - $version = new version "12.2.1"; # must be quoted! - print $version; # 12.2.1 - print $version->numify; # 12.002001 - if ( $version gt "v12.2" ) # true - - $vstring = new version qw(v1.2); # must be quoted! - print $vstring; # 1.2 - - $betaver = new version "1.2_3"; # must be quoted! - print $betaver; # 1.2_3 - - $perlver = new version 5.005_03; # must not be quoted! - print $perlver; # 5.5.30 - -=head1 DESCRIPTION - -Overloaded version objects for all versions of Perl. This module -implements all of the features of version objects which will be part -of Perl 5.10.0 except automatic v-string handling. See L<"Quoting">. - -=head2 What IS a version - -For the purposes of this module, a version "number" is a sequence of -positive integral values separated by decimal points and optionally a -single underscore. This corresponds to what Perl itself uses for a -version, as well as extending the "version as number" that is discussed -in the various editions of the Camel book. - -There are actually two distinct ways to initialize versions: - -=over 4 - -=item * Numeric Versions - any initial parameter which "looks like -a number", see L. - -=item * V-String Versions - any initial parameter which contains more -than one decimal point, contains an embedded underscore, or has a -leading 'v' see L. - -=back - -Both of these methods will produce similar version objects, in that -the default stringification will always be in a reduced form, i.e.: - - $v = new version 1.002003; # 1.2.3 - $v2 = new version "1.2.3"; # 1.2.3 - $v3 = new version v1.2.3; # 1.2.3 for Perl > v5.8.0 - $v4 = new version 1.2.3; # 1.2.3 for Perl > v5.8.0 - -Please see L for more details on how Perl will parse various -input values. - -Any value passed to the new() operator will be parsed only so far as it -contains a numeric, decimal, or underscore character. So, for example: - - $v1 = new version "99 and 94/100 percent pure"; # $v1 == 99.0 - $v2 = new version "something"; # $v2 == "" and $v2->numify == 0 - -However, see L for one case where non-numeric text is -acceptable when initializing version objects. - -=head2 Numeric Versions - -These correspond to historical versions of Perl itself prior to v5.6.0, -as well as all other modules which follow the Camel rules for the -$VERSION scalar. A numeric version is initialized with what looks like -a floating point number. Leading zeros B significant and trailing -zeros are implied so that a minimum of three places is maintained -between subversions. What this means is that any subversion (digits -to the right of the decimal place) that contains less than three digits -will have trailing zeros added to make up the difference. For example: - - $v = new version 1.2; # 1.200 - $v = new version 1.02; # 1.20 - $v = new version 1.002; # 1.2 - $v = new version 1.0023; # 1.2.300 - $v = new version 1.00203; # 1.2.30 - $v = new version 1.002_03; # 1.2.30 See L - $v = new version 1.002003; # 1.2.3 - -All of the preceeding examples except the second to last are true -whether or not the input value is quoted. The important feature is that -the input value contains only a single decimal. - -=head2 V-String Versions - -These are the newest form of versions, and correspond to Perl's own -version style beginning with v5.6.0. Starting with Perl v5.10.0, -this is likely to be the preferred form. This method requires that -the input parameter be quoted, although Perl > v5.9.0 can use bare -v-strings as a special form of quoting. - -Unlike L, V-String Versions must either have more than -a single decimal point, e.g. "5.6.1" B must be prefaced by a "v" -like this "v5.6" (much like v-string notation). In fact, with the -newest Perl v-strings themselves can be used to initialize version -objects. Also unlike L, leading zeros are B -significant, and trailing zeros must be explicitely specified (i.e. -will not be automatically added). In addition, the subversions are -not enforced to be three decimal places. - -So, for example: - - $v = new version "v1.2"; # 1.2 - $v = new version "v1.002"; # 1.2 - $v = new version "1.2.3"; # 1.2.3 - $v = new version "v1.2.3"; # 1.2.3 - $v = new version "v1.0003"; # 1.3 - -In additional to conventional versions, V-String Versions can be -used to create L. - -In general, V-String Versions permit the greatest amount of freedom -to specify a version, whereas Numeric Versions enforce a certain -uniformity. See also L for an additional method of -initializing version objects. - -=head2 Object Methods - -Overloading has been used with version objects to provide a natural -interface for their use. All mathematical operations are forbidden, -since they don't make any sense for versions. - -=over 4 - -=item * New Operator - Like all OO interfaces, the new() operator is -used to initialize version objects. One way to increment versions -when programming is to use the CVS variable $Revision, which is -automatically incremented by CVS every time the file is committed to -the repository. - -=back - -In order to facilitate this feature, the following -code can be employed: - - $VERSION = new version qw$Revision: 2.7 $; - -and the version object will be created as if the following code -were used: - - $VERSION = new version "v2.6"; - -In other words, the version will be automatically parsed out of the -string, and it will be quoted to preserve the meaning CVS normally -carries for versions. - -For the subsequent examples, the following two objects will be used: - - $ver = new version "1.2.3"; # see "Quoting" below - $beta = new version "1.2_3"; # see "Beta versions" below - -=over 4 - -=item * Stringification - Any time a version object is used as a string, -a stringified representation is returned in reduced form (no extraneous -zeros): - -=back - - print $ver->stringify; # prints 1.2.3 - print $ver; # same thing - -=over 4 - -=item * Numification - although all mathematical operations on version -objects are forbidden by default, it is possible to retrieve a number -which roughly corresponds to the version object through the use of the -$obj->numify method. For formatting purposes, when displaying a number -which corresponds a version object, all sub versions are assumed to have -three decimal places. So for example: - -=back - - print $ver->numify; # prints 1.002003 - -=over 4 - -=item * Comparison operators - Both cmp and <=> operators perform the -same comparison between terms (upgrading to a version object -automatically). Perl automatically generates all of the other comparison -operators based on those two. In addition to the obvious equalities -listed below, appending a single trailing 0 term does not change the -value of a version for comparison purposes. In other words "v1.2" and -"v1.2.0" are identical versions. - -=back - -For example, the following relations hold: - - As Number As String Truth Value - --------- ------------ ----------- - $ver > 1.0 $ver gt "1.0" true - $ver < 2.5 $ver lt true - $ver != 1.3 $ver ne "1.3" true - $ver == 1.2 $ver eq "1.2" false - $ver == 1.2.3 $ver eq "1.2.3" see discussion below - $ver == v1.2.3 $ver eq "v1.2.3" ditto - -In versions of Perl prior to the 5.9.0 development releases, it is not -permitted to use bare v-strings in either form, due to the nature of Perl's -parsing operation. After that version (and in the stable 5.10.0 release), -v-strings can be used with version objects without problem, see L<"Quoting"> -for more discussion of this topic. In the case of the last two lines of -the table above, only the string comparison will be true; the numerical -comparison will test false. However, you can do this: - - $ver == "1.2.3" or $ver == "v1.2.3" # both true - -even though you are doing a "numeric" comparison with a "string" value. -It is probably best to chose either the numeric notation or the string -notation and stick with it, to reduce confusion. See also L<"Quoting">. - -=head2 Quoting - -Because of the nature of the Perl parsing and tokenizing routines, -certain initialization values B be quoted in order to correctly -parse as the intended version, and additionally, some initial values -B be quoted to obtain the intended version. - -Except for L, any version initialized with something -that looks like a number (a single decimal place) will be parsed in -the same way whether or not the term is quoted. In order to be -compatible with earlier Perl version styles, any use of versions of -the form 5.006001 will be translated as 5.6.1. In other words, a -version with a single decimal place will be parsed as implicitly -having three places between subversions. - -The complicating factor is that in bare numbers (i.e. unquoted), the -underscore is a legal numeric character and is automatically stripped -by the Perl tokenizer before the version code is called. However, if -a number containing a single decimal and an underscore is quoted, i.e. -not bare, that is considered a L and the underscore is -significant. - -If you use a mathematic formula that resolves to a floating point number, -you are dependent on Perl's conversion routines to yield the version you -expect. You are pretty safe by dividing by a power of 10, for example, -but other operations are not likely to be what you intend. For example: - - $VERSION = new version (qw$Revision: 1.4)[1]/10; - print $VERSION; # yields 0.14 - $V2 = new version 100/9; # Integer overflow in decimal number - print $V2; # yields 11_1285418553 - -Perl 5.9.0 and beyond will be able to automatically quote v-strings -(which may become the recommended notation), but that is not possible in -earlier versions of Perl. In other words: - - $version = new version "v2.5.4"; # legal in all versions of Perl - $newvers = new version v2.5.4; # legal only in Perl > 5.9.0 - - -=head2 Types of Versions Objects - -There are two types of Version Objects: - -=over 4 - -=item * Ordinary versions - These are the versions that normal -modules will use. Can contain as many subversions as required. -In particular, those using RCS/CVS can use one of the following: - -=back - - $VERSION = new version qw$Revision: 2.7 $; - -and the current RCS Revision for that file will be inserted -automatically. If the file has been moved to a branch, the -Revision will have three or more elements; otherwise, it will -have only two. This allows you to automatically increment -your module version by using the Revision number from the primary -file in a distribution, see L. - -=over 4 - -=item * Beta versions - For module authors using CPAN, the -convention has been to note unstable releases with an underscore -in the version string, see L. Beta releases will test as being -newer than the more recent stable release, and less than the next -stable release. For example: - -=back - - $betaver = new version "12.3_1"; # must quote - -obeys the relationship - - 12.3 < $betaver < 12.4 - -As a matter of fact, if is also true that - - 12.3.0 < $betaver < 12.3.1 - -where the subversion is identical but the beta release is less than -the non-beta release. - -=head2 Replacement UNIVERSAL::VERSION - -In addition to the version objects, this modules also replaces the core -UNIVERSAL::VERSION function with one that uses version objects for its -comparisons. - -=head1 EXPORT - -None by default. - -=head1 AUTHOR - -John Peacock Ejpeacock@rowman.comE - -=head1 SEE ALSO - -L. - -=cut