NAME

       Dpkg::Version - handling and comparing dpkg-style version numbers

DESCRIPTION

       The Dpkg::Version module provides pure-Perl routines to compare dpkg-style version numbers
       (as used in Debian packages) and also an object oriented interface overriding perl
       operators to do the right thing when you compare Dpkg::Version object between them.

OBJECT INTERFACE

       my $v = Dpkg::Version->new($version, %opts)
           Create a new Dpkg::Version object corresponding to the version indicated in the string
           (scalar) $version. By default it will accepts any string and consider it as a valid
           version. If you pass the option "check => 1", it will return undef if the version is
           invalid (see version_check for details).

           You can always call $v->is_valid() later on to verify that the version is valid.

       boolean evaluation
           When the Dpkg::Version object is used in a boolean evaluation (for example in "if
           ($v)" or "$v || 'default'") it returns its string representation if the version stored
           is valid ($v->is_valid()) and undef otherwise.

       $v->is_valid()
           Returns true if the version is valid, false otherwise.

       $v->epoch(), $v->version(), $v->revision()
           Returns the corresponding part of the full version string.

       $v->is_native()
           Returns true if the version is native, false if it has a revision.

       $v1 <=> $v2, $v1 < $v2, $v1 <= $v2, $v1 > $v2, $v1 >= $v2
           Numerical comparison of various versions numbers. One of the two operands needs to be
           a Dpkg::Version, the other one can be anything provided that its string representation
           is a version number.

       "$v", $v->as_string(), $v->as_string(%options)
           Accepts an optional option hash reference, affecting the string conversion.

           Options:

           omit_epoch (defaults to 0)
                   Omit the epoch, if present, in the output string.

           omit_revision (defaults to 0)
                   Omit the revision, if present, in the output string.

           Returns the string representation of the version number.

FUNCTIONS

       All the functions are exported by default.

       version_compare($a, $b)
           Returns -1 if $a is earlier than $b, 0 if they are equal and 1 if $a is later than $b.

           If $a or $b are not valid version numbers, it dies with an error.

       version_compare_relation($a, $rel, $b)
           Returns the result (0 or 1) of the given comparison operation. This function is
           implemented on top of version_compare().

           Allowed values for $rel are the exported constants REL_GT, REL_GE, REL_EQ, REL_LE,
           REL_LT. Use version_normalize_relation() if you have an input string containing the
           operator.

       my $rel = version_normalize_relation($rel_string)
           Returns the normalized constant of the relation $rel (a value among REL_GT, REL_GE,
           REL_EQ, REL_LE and REL_LT). Supported relations names in input are: "gt", "ge", "eq",
           "le", "lt", ">>", ">=", "=", "<=", "<<". ">" and "<" are also supported but should not
           be used as they are obsolete aliases of ">=" and "<=".

       version_compare_string($a, $b)
           String comparison function used for comparing non-numerical parts of version numbers.
           Returns -1 if $a is earlier than $b, 0 if they are equal and 1 if $a is later than $b.

           The "~" character always sort lower than anything else. Digits sort lower than non-
           digits. Among remaining characters alphabetic characters (A-Za-z) sort lower than the
           other ones. Within each range, the ASCII decimal value of the character is used to
           sort between characters.

       version_compare_part($a, $b)
           Compare two corresponding sub-parts of a version number (either upstream version or
           debian revision).

           Each parameter is split by version_split_digits() and resulting items are compared
           together. As soon as a difference happens, it returns -1 if $a is earlier than $b, 0
           if they are equal and 1 if $a is later than $b.

       my @items = version_split_digits($version)
           Splits a string in items that are each entirely composed either of digits or of non-
           digits. For instance for "1.024~beta1+svn234" it would return ("1", ".", "024",
           "~beta", "1", "+svn", "234").

       my ($ok, $msg) = version_check($version)
       my $ok = version_check($version)
           Checks the validity of $version as a version number. Returns 1 in $ok if the version
           is valid, 0 otherwise. In the latter case, $msg contains a description of the problem
           with the $version scalar.

CHANGES

   Version 1.01
       New argument: Accept an options argument in $v->as_string().

       New method: $v->is_native().

AUTHOR

       Don Armstrong <don@donarmstrong.com>, Colin Watson <cjwatson@debian.org> and Raphaël
       Hertzog <hertzog@debian.org>, based on the implementation in dpkg/lib/version.c by Ian
       Jackson and others.