Hi Monks,

I have a question about some code I saw in Mojo::File. In the slurp method, you see this:

sub slurp {
  my $self = shift;
 
  CORE::open my $file, '<', $$self or croak qq{Can't open file "$$self
+": $!};
  my $ret = my $content = '';
  <b>while ($ret = $file->sysread(my $buffer, 131072, 0)) { $content .
+= $buffer }</b>
  croak qq{Can't read from file "$$self": $!} unless defined $ret;
 
  return $content;
}

[download]

Inside the while, you see my $buffer used as the first argument to sysread, and then used in the body of the while loop. I've never seen this before, where you declare a variable as an argument and then access it later. Can anyone explain how this works? Is the body of the while loop able to access $buffer because the while loop's scope includes anything in the parentheses or the body of the loop?

In reply to Declare my variable in sysread - Mojo::File::slurp by srchulo

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