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 $limit¶
The "minimum_syntax_version" method will explicitly test only the
Document's syntax to determine it's minimum version, to the extent that this
is possible.
It takes an optional parameter of a version object defining the the lowest known
current value. For example, if it is already known that it must be 5.006 or
higher, then you can provide a param of qv(5.006) and the method will not run
any of the tests below this version. This should provide dramatic speed
improvements for large and/or complex documents.
The limitations of parsing Perl mean that this method may provide artifically
low results, but should not artificially high results.
For example, if "minimum_syntax_version" returned 5.006, you can be
confident it will not run on anything lower, although there is a chance that
during actual execution it may use some untestable feature that creates a
dependency on a higher version.
Returns a version object, false if no dependencies could be found, or
"undef" on error.
minimum_external_version¶
WARNING: This method has not been implemented. Any attempted use will
throw an exception
The "minimum_external_version" examines code for dependencies on other
external files, and recursively traverses the dependency tree applying the
same tests to those files as it does to the original.
Returns a "version" object, false if no dependencies could be found,
or "undef" on error.
version_markers¶
This method returns a list of pairs in the form:
($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>
SEE ALSO¶
perlver - the command-line script for running "Perl::MinimumVersion"
on your code.
Perl::MinimumVersion::Fast - another module which does the same thing. It's a
lot faster, but only supports Perl 5.8.1+.
<
http://ali.as/>, PPI, version
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.