in reply to Re: use subs
in thread use subs

I had a nice version that would check the number of parameters passed and call CORE::open with the correct number of parameters but after reading Arrays are not lists I realized that I could shorten it greatly by using @_[0..$#_]. Thanks tilly++ (where ever you are) for writing such a great node. Thanks Gilimanjaro++ for pointing it out.
use subs 'open';
sub open {
  my $params = scalar @_;
  print "received $params parameters...\n";
  my $filehandle = shift;
  print "received filehandle $filehandle...\n";
  print "received list @_[0..$#_]...\n";
  my $return;
  $return = CORE::open($filehandle,@_[0..$#_]);
  return $return;
}
my $result;
$result = open(TEST);
print $result,$/;
close(TEST);
$result = open(TEST, "test.txt");
print $result,$/;
close(TEST);
$result = open(TEST, "<test.txt");
print $result,$/;
close(TEST);
$result = open(TEST, "<", "test.txt");
print $result,$/;
close(TEST);

[download]
I have left all the print statements in there for debugging purposes.

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Re^3: use subs
by Aristotle (Chancellor) on Jan 24, 2003 at 17:02 UTC
    Did I miss something (upd.: yes, I did) or couldn't this be cut down to simply: 
    use subs 'open';
sub open {
    print @_ . "parameters: @_\n";
    CORE::open(@_[0..$#_]);
}

    [download]
    (I didn't test anything, so I may well be way off the mark.)

    Makeshifts last the longest.

[reply]
[d/l]
      No, it can't. The CORE::open does not succeed if you do not hand it a scalar filehandle.

      use subs 'open';
sub open {
  print @_ . " parameters: @_\n";
  my $filehandle = shift;
  CORE::open($filehandle,@_[0..$#_]);
}
sub open2 {
    print @_ . " parameters: @_\n";
    CORE::open(@_[0..$#_]);
}

my $result;

print "Testing open...\n";
print open(TEST),$/;
print open(TEST, "test.txt"),$/;
print open(TEST, "<test.txt"),$/;
print open(TEST, "<", "test.txt"),$/;
print $/;
print "Testing open2...\n";
print open2(TEST),$/;
print open2(TEST, "test.txt"),$/;
print open2(TEST, "<test.txt"),$/;
print open2(TEST, "<", "test.txt"),$/;
print $/;

      [download]

[reply]
[d/l]
Re^3: use subs
by blahblahblah (Priest) on Apr 08, 2005 at 15:13 UTC
    I figured that I would update this for the benefit of anyone who comes along and decides to try it. I went with Mr. Muskrat's idea and it has worked great. Recently I had a problem handling a first arg that is an undefined scalar, for example: 
    open(my $file, "<", $file);

    [download]
    Again tilly came to the rescue: see anonymous filehandle for overridden open sub.

    -Joe

[reply]
[d/l]

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