$ cat test.pl #!/usr/bin/perl use strict; use warnings; # Requires 5.6.0 my $a = 5; -e -f -s $0 and print "0\n"; # Requires 5.8.0 1 < $a < 10 and print "1\n"; # Requires 5.31.11 / 5.32.0 $a //= 42; # Requires 5.10.0 $a =~ s{0\K}{}; # Requires 5.10.0 $b = $a =~ s{0}{1}r; # Requires 5.14.0 $ perlver --blame test.pl ------------------------------------------------------------ File : test.pl Line : 12 Char : 12 Rule : _regex Version : 5.013002 ------------------------------------------------------------ s{0}{1}r ------------------------------------------------------------ #### $ perlver-fast test.pl test.pl: 5.010 #### #!/usr/bin/env perl use strict; use warnings; use Getopt::Long qw(:config bundling passthrough); use Perl::MinimumVersion::Fast; GetOptions ( "e:s" => \my $expr, "v" => \my $verbose, ) or die; if (@ARGV) { report ($_, $_) for @ARGV; } elsif ($expr) { report ("-e", \$expr); } else { my $src = do { local $/; <> }; report ("STDIN", \$src); } sub report { my ($in, $src) = @_; my $v = Perl::MinimumVersion::Fast->new ($src); printf "%s: %s / %s\n", $in, $v->minimum_version, $v->minimum_syntax_version; $verbose or return; my @markers = $v->version_markers; while (@markers) { my ($pv, $m) = splice @markers, 0, 2; printf "%-10s %s\n", $pv, $_ for @$m; } } #### $ perlver-fast -e '$a //= 4' -e: 5.010 / 5.010 #### $ perlver-fast -ve '$a //= 4; package foo 0.04 { 1; }' -e: 5.014 / 5.014 5.010 //= operator 5.012 package NAME VERSION 5.014 package NAME VERSION BLOCK #### $ perlver-fast -ve '$a = "fo" =~ s{f\K}{o}r' -e: 5.006 / 5.006