conditional expressions (RE: Loop-and-a-half (Re: Curious assignment behaviour))

Greg Ewing greg at cosc.canterbury.ac.nz
Thu Oct 18 02:57:44 CEST 2001


John Roth wrote:
> 
> "Paul Boddie" <paul at boddie.net> wrote in message
> news:23891c90.0110170317.1e18fae5 at posting.google.com...
> >
> > It seems to me, from code I've seen and written, that the C- and
> > Java-style ... ? ... : ... construct is most frequently used in cases
> > where one is testing for NULL (or null)
> 
> Many instances of this are already handled by the short-circuit
> 'and' and 'or' operators. These operators have well-known
> deficiencies...

Maybe we could do with an operator like 'or' except
that it compares its first operand with None instead
of just testing it for trueness. I suggest

  x else y

or, if you want to keep 'else' for a possible future
reconsideration of if-then-else and don't mind a new
keyword,

  x otherwise y

-- 
Greg Ewing, Computer Science Dept, University of Canterbury,	  
Christchurch, New Zealand
To get my email address, please visit my web page:	  
http://www.cosc.canterbury.ac.nz/~greg



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