#!/usr/bin/perl --
use strict; use warnings;
my $dita = <<'__DITA__';
mono-basic-2.10
mono-2.10.2-r1
mono-2.10.5
__DITA__
open my $data => '<', \$dita or die $!;
while( my $line = <$data> ){
    if( my ($version) = $line =~ /^[a-z-]+(\d.*)\s*$/ ){
        print ">>$version<<\n"
    }
}
__END__
>>2.10<<
>>2.10.2-r1<<
>>2.10.5<<