Hi,

as a side note, your anonymous function does not really act as a closure: 

my $fh = IO::File->new($filename, 'r');

my $fh_iterator = sub {
    my $fh = shift;

    my $line = $fh->getline;
}

while (my $line = $fh_iterator->($fh)) {
    # do stuff to $line
}

[download]

because you are passing $fh each time to the sub (and you have to, you actually get a fresh copy of $fh each time the anonymous subroutine is called).

If you want it to act as a closure, you may do something like this (untested):

sub create_iterator{
   my $filename = shift;
   my $fh = IO::File->new($filename, 'r');
   return sub { 
      my $line = $fh->getline;
   }
}

my $fh_iterator = create_iterator($file_name);

while (my $line = $fh_iterator->()) {
    # do stuff to $line
}

[download]

Now, $fh is really a persistent variable within the sub scope, this is a real closure.

In reply to Re: Iterator to parse multiline string with \\n terminator by Laurent_R
in thread Iterator to parse multiline string with \\n terminator by three18ti

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