http://www.perlmonks.org?node_id=1000756


in reply to Perl noob struggling to loop through an array

$ echo ">Sequence_Header_A
DNAsequence
>Sequence_Header_B
DNAsequence
>Sequence_Header_C
DNAsequence"  |  perl -e'

while ( <> ) {
    next unless /^>/;
    ( my $format = $_ ) =~ s/\n/_%d\n%s\n/;
    chomp( my @data = split /(?=e)/, <> );
    my $count;                            
    printf $format, ++$count, $_ for @data;
    }                                      
'
>Sequence_Header_A_1
DNAs
>Sequence_Header_A_2
equ
>Sequence_Header_A_3
enc
>Sequence_Header_A_4
e
>Sequence_Header_B_1
DNAs
>Sequence_Header_B_2
equ
>Sequence_Header_B_3
enc
>Sequence_Header_B_4
e
>Sequence_Header_C_1
DNAs
>Sequence_Header_C_2
equ
>Sequence_Header_C_3
enc
>Sequence_Header_C_4
e

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