Hmm, I'm not sure I understand your question. Fixing the syntax errors in your code (s.below) makes it print out exactly what you seem to expect.

my %hash    = (
 'mus09r' => [ '0,-464,AAACCATCTTGAAAC',
               '0,-350,GGTTCAGGATGGTTT',
               '0,-75,AAAACATCGTGACAC' ],
);

while (my ($file,$val) = each %hash) {
      print ">dataset\n";
      print "$file\n";
      print ">instances\n";
      print join("\n",@{$val}),"\n";
}

[download]

If what you're looking to do is put the text into a variable instead, simply append to that variable instead of printing directly.

use Data::Dumper;

my %hash    = (
 'mus09r' => [ '0,-464,AAACCATCTTGAAAC',
               '0,-350,GGTTCAGGATGGTTT',
               '0,-75,AAAACATCGTGACAC' ],
);

my $string;
while (my ($file,$val) = each %hash) {
      $string.=">dataset\n".
               "$file\n".
               ">instances\n".
               join("\n",@{$val}).
               "\n";
}
print Dumper $string;

[download]

Update: Appending to string instead of replacing it every hash iteration, as per Mandrake's suggestion (note to self: Duh!).


Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it. -- Brian W. Kernighan

In reply to Re: Creating a Stringified Variable by tirwhan
in thread Creating a Stringified Variable from a Data Structure by monkfan

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