in reply to Re^5: Incrementing a large number without Math::BigInt
in thread Incrementing a large number without Math::BigInt

|, &, ^ and ~ also work on strings. 

>perl -e "print 'A'|'B'
C
>perl -e "print 'C'&'E'
A
>perl -e "print 'A'^' '
a

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I wish << and >> did as well.

Documented in perlop

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Re^7: Incrementing a large number without Math::BigInt
by Cap'n Steve (Friar) on Apr 26, 2006 at 05:45 UTC
    Yes, I actually noticed this node while searching for a solution to my problem. But isn't that more of an ASCII feature than a Perl one? I wonder why the deincrementing and bit shifting don't work.
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      ASCII has nothing to do with it. You can use those operators on any string of bytes, whether the data is ASCII, the result of inet_aton or a struct to pass to a system call. The operators work independantly of how the data is interpreted.

      Now, $letter ^ ' ' will not toggle the case of the letter in all encodings, but that's a (simple) algorithm that uses ^ and not ^ proper.

      Here's an example which demonstrates that ^ work no matter how the data was encoded: 

      use Socket qw( inet_aton inet_ntoa );

my $ip        = inet_aton('10.0.0.155');
my $mask      = inet_aton('255.255.255.240');
my $broadcast = $ip | ~$mask;

print(inet_ntoa($broadcast), "\n");  # 10.0.0.159

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      It's definitely a language feature, and I believe an uncommon one. You can't do that in C or Java, for example.

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