Re: Infinite lists (was Re: RFC 24 (v1) Semi-finite (lazy) lists)

[John Porter]

Jeremy Howard wrote:
> The reason that having (1..) implies having (..-1) is that if you allow
> (1..), then this is a valid construct:
> 
>   @dot_dot_neg_one = reverse (map {-$_} (1..));
> 
> which is identical to (..-1)! 

No, NOT identical.  The same set of numbers, yes, but generated in
the opposite order.   (..-1) should generate -INF first, but obviously
it can't do that.  (..$n) is an impossible construct, and should be
a fatal error -- presuming it even gets past the lexer...

-- 
John Porter