The London Perl and Raku Workshop takes place on 26th Oct 2024. If your company depends on Perl, please consider sponsoring and/or attending.


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


    use Perl::MinimumVersion::Fast;

    my $p = Perl::MinimumVersion::Fast->new($filename);
    print $p->minimum_version, "\n";


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

Perl::MinimumVersion::Fast is an alternative fast & lightweight implementation of Perl::MinimumVersion.

This module supports only Perl 5.8.1+. If you want to support Perl 5.6, use Perl::MinimumVersion instead.

In 2013, you don't need to support Perl 5.6 in most of case.


my $p = Perl::MinimumVersion::Fast->new($filename);
my $p = Perl::MinimumVersion::Fast->new(\$src);

Create new instance. You can create object from $filename and \$src in string.


Get a minimum perl version the code required.


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, undef if no dependencies could be found.


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.

Returns a version object, undef if no dependencies could be found.


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.


Perl::MinimumVersion::Fast is faster than Perl::MinimumVersion. Because Perl::MinimumVersion::Fast uses Compiler::Lexer, that is a Perl5 lexer implemented in C++. And Perl::MinimumVersion::Fast omits some features implemented in Perl::MinimumVersion.

But, but, Perl::MinimumVersion::Fast is really fast.

                                Rate Perl::MinimumVersion Perl::MinimumVersion::Fast
    Perl::MinimumVersion       5.26/s                   --                       -97%
    Perl::MinimumVersion::Fast  182/s                3365%                         --


Copyright (C) tokuhirom.

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


Most of documents are taken from Perl::MinimumVersion.


tokuhirom <>


This module using Compiler::Lexer as a lexer for Perl5 code.

This module is inspired from Perl::MinimumVersion.