Please read about "$_" ... IT is the "default" for the "shift" function ...
Perl tries to help ... The Camel has a good discussion on subroutines (ref.
Ch 2 "Subroutines" ) ... also see Ch 2 "Global Special Variables"
Before I coded any Perl I found the Llama book very helpful and found myself
using it for a reference for a long time ...
John W Moon
-----Original Message-----
From: Hassan Eshtiaghi [Nick] [mailto:[EMAIL PROTECTED]]
Sent: June 07, 2001 18:13
To: [EMAIL PROTECTED]
Subject: Decimal To Binary
The following sub is in the Perl Cookbook, section 2.4.1(Converting Between
Binary and Decimal). When I call the sub I get the correct output, but if I
use the same unpack and pack functions as stand-alone statements, outside a
sub, the output is always 0(zero). What am missing?
sub dec2bin {
my $str = unpack("B32", pack("N", shift));
$str =~ s/^0+(?=\d)//; # otherwise you'll get leading zeros
return $str;
}
$binstr = dec2bin(54);
print $binstr # This gives me the right output.
-----------------------------------
Using the same concept outside the sub:
$str = 54;
$str = unpack("B32", $pack("N", shift));
$str =~ s/^0+(?=\d)//; # otherwise you'll get leading zeros
printf("%s \n", $str); #This gives me 0.
