Ubuntu Manpage: Perl::MinimumVersion - Find a minimum required version of perl for Perl code

Provided by: libperl-minimumversion-perl_1.40-1_all

NAME

       Perl::MinimumVersion - Find a minimum required version of perl for Perl code

SYNOPSIS

         # Create the version checking object
         $object = Perl::MinimumVersion->new( $filename );
         $object = Perl::MinimumVersion->new( \$source  );
         $object = Perl::MinimumVersion->new( $ppi_document );

         # Find the minimum version
         $version = $object->minimum_version;

DESCRIPTION

       "Perl::MinimumVersion" takes Perl source code and calculates the minimum version of perl
       required to be able to run it. Because it is based on PPI, it can do this without having
       to actually load the code.

       Currently it tests both the syntax of your code, and the use of explicit version
       dependencies such as "require 5.005".

       Future plans are to also add support for tracing module dependencies.

       Using "Perl::MinimumVersion" is dead simple, the synopsis pretty much covers it.

       The distribution comes with a script called perlver, which is the easiest way to run
       "Perl::MinimumVersion" on your code:

        % perlver lib/Foo/Bar.pm

       See the documentation for perlver for more details.

METHODS

new
# Create the version checking object
$object = Perl::MinimumVersion->new( $filename );
$object = Perl::MinimumVersion->new( \$source );
$object = Perl::MinimumVersion->new( $ppi_document );

The "new" constructor creates a new version checking object for a PPI::Document. You can
also provide the document to be read as a file name, or as a "SCALAR" reference containing
the code.

Returns a new "Perl::MinimumVersion" object, or "undef" on error.

Document
The "Document" accessor can be used to get the PPI::Document object back out of the
version checker.

minimum_version
The "minimum_version" method is the primary method for finding the minimum perl version
required based on "all" factors in the document.

At the present time, this is just syntax and explicit version checks, as Perl::Depends is
not yet completed.

Returns a version object, or "undef" on error.

minimum_explicit_version
The "minimum_explicit_version" method checks through Perl code for the use of explicit
version dependencies such as.

use 5.006;
require 5.005_03;

Although there is almost always only one of these in a file, if more than one are found,
the highest version dependency will be returned.

Returns a version object, false if no dependencies could be found, or "undef" on error.

minimum_syntax_version $limit
The "minimum_syntax_version" method will explicitly test only the Document's syntax to
determine it's minimum version, to the extent that this is possible.

It takes an optional parameter of a version object defining the lowest known current
value. For example, if it is already known that it must be 5.006 or higher, then you can
provide a param of qv(5.006) and the method will not run any of the tests below this
version. This should provide dramatic speed improvements for large and/or complex
documents.

The limitations of parsing Perl mean that this method may provide artificially low
results, but should not artificially high results.

For example, if "minimum_syntax_version" returned 5.006, you can be confident it will not
run on anything lower, although there is a chance that during actual execution it may use
some untestable feature that creates a dependency on a higher version.

Returns a version object, false if no dependencies could be found, or "undef" on error.

minimum_external_version
WARNING: This method has not been implemented. Any attempted use will throw an exception

The "minimum_external_version" examines code for dependencies on other external files, and
recursively traverses the dependency tree applying the same tests to those files as it
does to the original.

Returns a "version" object, false if no dependencies could be found, or "undef" on error.

version_markers
This method returns a list of pairs in the form:

($version, \@markers)

Each pair represents all the markers that could be found indicating that the version was
the minimum needed version. @markers is an array of strings. Currently, these strings
are not as clear as they might be, but this may be changed in the future. In other words:
don't rely on them as specific identifiers.

BUGS

       Perl::MinimumVersion does a reasonable job of catching the best-known explicit version
       dependencies.

       However it is exceedingly easy to add a new syntax check, so if you find something this is
       missing, copy and paste one of the existing 5 line checking functions, modify it to find
       what you want, and report it to rt.cpan.org, along with the version needed.

       I don't even need an entire diff... just the function and version.

TO DO

       Write lots more version checkers

       - Perl 5.10 operators and language structures

       - Three-argument open

       Write the explicit version checker

       Write the recursive module descend stuff

       _while_readdir for postfix while without brackets

       Check for more 5.12 features (currently only detecting "package NAME VERSION;", "...", and
       "use feature ':5.12'")

SUPPORT

       All bugs should be filed via the CPAN bug tracker at

       <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Perl-MinimumVersion>

       For other issues, or commercial enhancement or support, contact the author.

AUTHORS

       Adam Kennedy <adamk@cpan.org>

REPOSITORY

       <https://github.com/neilbowers/Perl-MinimumVersion>

COPYRIGHT

       Copyright 2005 - 2014 Adam Kennedy.

       This program is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself.

       The full text of the license can be found in the LICENSE file included with this module.