What is: {% use

johnnywang has asked for the wisdom of the Perl Monks concerning the following question:

while I was looking at the source of POE::Driver::SysRW, I saw the line: {% use_bytes %}, what is the syntax? what does it mean? Thanks. The full method is as follows:

sub put {
  my ($self, $chunks) = @_;
  my $old_queue_octets = $self->[TOTAL_OCTETS_LEFT];

  {% use_bytes %}

  foreach (grep { length } @$chunks) {
    $self->[TOTAL_OCTETS_LEFT] += length;
    push @{$self->[OUTPUT_QUEUE]}, $_;
  }

  if ($self->[TOTAL_OCTETS_LEFT] && (!$old_queue_octets)) {
    $self->[CURRENT_OCTETS_LEFT] = length($self->[OUTPUT_QUEUE]->[0]);
    $self->[CURRENT_OCTETS_DONE] = 0;
  }

  $self->[TOTAL_OCTETS_LEFT];
}
[download]

Comment on What is: {% use_bytes %}? Download Code

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Re: What is: {% use_bytes %}? by bmann (Priest) on Mar 30, 2005 at 00:10 UTC
It is a POE::Preprocessor directive. It's POE's way to `use bytes;` if the bytes pragma exists, or to fail gracefully if it does not exist (pre 5.6, IIRC). Update: You find `use POE::Preprocessor ( isa => "POE::Macro::UseBytes" );` [download] early on in the source of POE::Driver::SysRW, but for some reason POE::Macro::UseBytes is not indexed by CPAN. Download the source of POE if you want to see UseBytes.pm	[reply] [d/l] [select]
Re: What is: {% use_bytes %}? by ambs (Pilgrim) on Mar 30, 2005 at 08:07 UTC
The POE code is filtered? Alberto Simões	[reply]