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Re: "Secret" operators

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From:
Yitzchak Scott-Thoennes
Date:
February 3, 2005 12:08
Subject:
Re: "Secret" operators
Message ID:
20050203200739.GD3340@efn.org
On Wed, Feb 02, 2005 at 04:20:05PM +0200, Vladi Belperchinov-Shabanski wrote:
> On Wed, 2 Feb 2005 12:33:35 +1100 (EST)
> Andrew Savige <ajsavige@yahoo.com.au> wrote:
> 
> > Jos_ Castro wrote:
> > > Apart from the "secret eskimo greeting" and the "goatse operator",
> > > can anyone tell me about other "secret" operators?
> > 
> > Let's not forget the Ton Hospel "high-precedence decrement"
> > operator ~- invented during a golf tournament (anyone remember
> > which one?).
> > 
> > IIRC, Ton's ~- invention allows you to eliminate the parens in:
> > 
> >     $y = ($x-1)*4;
> > 
> > by using instead:
> > 
> >     $y = ~-$x*4;
> > 
> > saving a whopping two strokes. This trick should work on any
> > twos complement machine -- and I'm not aware of any perl running
> > on any non twos complement machine.
> 
> will not work if $x < 0

Except under "use integer".  A little known fact is that perl's bitops
cast operands to unsigned integers without "use integer" and to signed
integers with "use integer".

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