Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!rbj
From: rbj@uunet.UU.NET (Root Boy Jim)
Newsgroups: comp.lang.perl
Subject: Re: Even Parity Table Generation
Message-ID: <122374@uunet.UU.NET>
Date: 11 Feb 91 21:20:34 GMT
References: <121817@uunet.UU.NET> <11387@jpl-devvax.JPL.NASA.GOV>
Organization: UUNET Communications Services, Falls Church, VA
Lines: 38

In article <11387@jpl-devvax.JPL.NASA.GOV> lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall) writes:
>In article <121817@uunet.UU.NET> rbj@uunet.UU.NET (Root Boy Jim) writes:
>: I hereby request another function: chr(), the opposite of ord().
>: Either that, or get rid of ord.
>
>How 'bout:
>
>	sub chr {sprintf("%c",$_[0]);}

Yes, I know that it can be done that way, or I can use pack, as I did.
I suppose I can use use vec. Which is most efficient?

However, I would rather have one primitive to SAY WHAT I MEAN rather than
having to simulate it from a subroutine call and a more general primitive.

I have heard that ord preceded pack/unpack and that's why it's there.

>: Anyway, here it is:
>[recursive solution omitted]
>
>I'd just say:
>
>[iterative solution deleted]

Well, if we want to slice bits, how about:

#!/usr/bin/perl  
for (0 .. 127) { 
	$x = $_; 
	$_ ^= $_>>4; 
	$_ ^= $_>>2; 
	$_ ^= $_>>1;  
	printf "%x %x\n", $x, $x ^ (($_ & 1) << 7);
} 
-- 
	Root Boy Jim Cottrell <rbj@uunet.uu.net>
	I got a head full of ideas
	They're driving me insane