#!perl -w

use strict;

for my $name (<DATA>) {
   chomp $name;
   my %parts;
   $name =~ s/(.*)(\.[^.]*)/$1/;
   $parts{"suffix"} = $2 or die "Not a valid file name: $name";
   $parts{"prefix"} = [];
   $parts{"number"} = [];
   while ($name =~ s/^(\D*)(\d+)//) {
      push @{$parts{"prefix"}}, $1;
      push @{$parts{"number"}}, $2;
   }
   $name and die "Invalid file name format. Rest '$name' remained";
   print "Filename splits as follows: [" 
       . join("][", 
            map { "(" . $parts{"prefix"}->[$_] . ")(" 
                      . $parts{"number"}->[$_] . ")" } 0..@{$parts{"number"}}-1)
       . "]<"
       . $parts{"suffix"} . ">\n";
}

__DATA__
01-html02.html
01-htm23-43.htm
01-file-01.html

##</code><code>##

++$parts{"number"}->[$i];
$filename = join('',
               map { $parts{"prefix"}->[$_]                    
                   . $parts{"number"}->[$_] }                  
                               0..@{$parts{"number"}}-1)        
            . $parts{"suffix"};