use ihb::List::Util qw/ group transpose /;
use List::Util qw/ max sum /;

my @files = sort qw/
    B           Digest      Filter     MIME       SDBM_File  Time     util
    ByteLoader  DynaLoader  GDBM_File  NDBM_File  Safe       Unicode
    Cwd         Encode      I18N       ODBM_File  Socket     XS
    DB_File     Errno       IO         Opcode     Storable   attrs
    Data        Fcntl       IPC        POSIX      Sys        re
    Devel       File        List       PerlIO     Thread     threads
/;

my $width = 55;
my $padding = 2;

# Columnize
my (@cols, @widths);
for (my $rows = 1; 1; $rows++) {
    @cols = group($rows, @files);
    @{$cols[-1]} = grep defined, @{$cols[-1]};

    @widths = map max(map length, @$_), @cols;
    
    my $tw = sum(@widths) + $padding * (@widths - 1);
    last if $tw < $width or $rows == @files;
}

# Format columns
for (0 .. $#cols) {
    my $format = "%-$widths[$_]s";
    for (@{$cols[$_]}) {
        $_ = sprintf $format, $_;
    }
}

# Output rows
{
    local $" = ' ' x $padding;
    print "@$_\n" for transpose(@cols);
}