Patch: use the last element of the array for a counter.

sub TIEHANDLE($;$) 
{
    my $pkg = shift;
    my $ref = shift || [];
    push @{$ref}, 0;

    bless( $ref, $pkg );
}

sub READLINE 
{
    my $ref = shift;
    return @{$ref} > 1 ? ">Seq" . ++$ref->[-1] . "\n" . shift (@{$ref}
+) . "\n" : undef;
}
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so

use Tie::Handle::FromArray;

my $fh = new Tie::Handle::FromArray ( ["AAAAAAAAAAAAAAA", "AAAAAAAGGAA
+ACCA"] );
while (<$fh>) { print; }
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prints

>Seq1
AAAAAAAAAAAAAAA
>Seq2
AAAAAAAGGAAACCA
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