> use strict;
> use warnings;
> use Bio::Seq;
> use Bio::SeqFeature::Generic;

> select(STDERR);
> $| = 1;
> select(STDOUT);
> $| = 1;

> my $seq = Bio::Seq->new(
>    -seq => 'AAAAAAAAAAAAAAAAAAAACCCCCCTTTT',
> );

> # A feature of the sequence spanning the 'CCCCCCTTTT' region
> my $feat = Bio::SeqFeature::Generic->new(
>     -start       => 21,
>     -end         => 30,
>     -strand      => 1,
> );
> print "Attaching feature to sequence... ";
> $seq->add_SeqFeature($feat);
> print "done!\n\n";

> # A subfeature of the feature, spanning 'CCCCCC'
> my $subfeat = Bio::SeqFeature::Generic->new(
>     -start      => 1,
>     -end        => 6,
> #    -start       => 21,
> #    -end         => 26,
> );
> print "Attaching subfeature to feature... ";
> $feat->add_SeqFeature($subfeat);
> print "done!\n\n";