Since EDL's deal with video/film their smallest quantity is the frame (pls nobody remind me about fields!!) , and depending on the format , one second of footage is 24, or 25, or 30 frames. What I was searching for was a module that allowed creating a counter that one can set arbitary values for the carry to next column. For SMPTE PAL video, this would mean 25frames to each second, 60 seconds to each minute, 60 minutes to the hour.

Ultimatly I rolled a module that creates edit objects with properties like in and out point. To apply the range logic to them, timecode in the format HH:MM:SS:FF was converted to integers in its lowest atomic - the frame.

package timecode;

our $fps = 25;

sub fps {
 $fps = $_[1];
}

sub _smpte2int {
 my $tc = shift;
 my @hmsf = split ':' , $tc;
 my ($hours , $mins, $secs , $frames);
 $hours = 60*60*$fps*$hmsf[0];
 $mins  = 60*$fps*   $hmsf[1];
 $secs  = $fps  *  $hmsf[2];
 $frames= $hmsf[3];
 return $hours+$mins+$secs+$frames;
}

sub _int2smpte {
 my $int = shift;
 my ($hours , $mins , $secs , $frames);
 my $r;
 $r = $int % ($fps*60*60);
 
 $hours =   sprintf '%02d' , int ( ($int-$r) / ($fps*60*60) ) ; 
 
 $int = $r;
 $r = $int % ($fps*60);
 $mins = sprintf '%02d' , int ( ($int-$r) / ($fps*60) );

 $int = $r;
 $r = $int % ($fps);
 $secs = sprintf '%02d' , int ( ($int-$r) / ($fps) );
 
 $int = $r;
 $frames = sprintf '%02d' , $int;
 return  join ":",  $hours,$mins,$secs,$frames ;

} 

sub new {
 my $self = shift;
 my %tc = @_;
 #@tc{qw/in out/} = ( _smpte2int($in) ,  _smpte2int($out) );
 die @_  unless ( defined $tc{in} );
 die @_ unless (defined $tc{out});

 $tc{in} = _smpte2int($tc{in});
 $tc{out} = _smpte2int($tc{out});
 return bless \%tc, $self; 
}

sub copy {
 my $self=shift;
 
 my $ref =shift;
 my %tc = %$ref;
 return bless \%tc, $self;
}

sub asEdl {
  my $self = shift;
 my $in = _int2smpte($self->{in});
 my $out= _int2smpte($self->{out});
 

 return join '' , $self->{event}, ' 'x2,
        $self->{roll}, ' 'x6,
        $self->{channel}, ' 'x5,
        $self->{type}, ' 'x8,
        "$in $out $in $out    \n";
}

sub check { 
 my $self = shift;
 return _int2smpte ( $self->{in} ) , _int2smpte( $self->{out} );
}
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There's a question in here somewhere I know it... the wisdom I seek is the name of the module I've made bastardized hack of. I'm not sure of the best words to describe it... counters of arbitary range? no... erm... help!