Set operation like cartesian product

[H. S. Teoh]

On Thu, Feb 28, 2013 at 03:01:48PM -0800, H. S. Teoh wrote:
> On Thu, Feb 28, 2013 at 09:20:52PM +0100, Andrea Fontana wrote:
> > On Thursday, 28 February 2013 at 18:23:04 UTC, H. S. Teoh wrote:
> [...]
> > >auto triangularProduct2(R1,R2)(R1 r1, R2 r2)
> > >	if (isForwardRange!R1)
> > >{
> > >	return map!(function(a) => zip(take(a[1].save, a[0]),
> > >repeat(a[2])))(
> > >			zip(sequence!"n"(1), repeat(r1.save), r2)
> > >		)
> > >		.joiner();
> > >}
> > >
> > >As above, both ranges can be infinite, only the first one needs to
> > >be a
> > >forward range.
> > >
> > >Hope this helps. ;-)
> > >
> > >
> > >T
> > 
> > triangulaProduct2 for [0,1,2,3] and [0,1,2,3] doesn't give (0,0)
> > (1,1) (2,2) (3,3)
> > 
> > :)
> 
> Ahhh, slight mistake there, it should be:
> 
> auto triangularProduct2(R1,R2)(R1 r1, R2 r2)
> 	if (isForwardRange!R1)
> {
> 	return map!(function(a) => zip(take(a[1].save, a[0]+1), repeat(a[2])))(
> 			zip(sequence!"n"(1), repeat(r1.save), r2)
[...]

Argh. Another mistake. The above line should read:

 			zip(sequence!"n"(0), repeat(r1.save), r2)

:-/


T

-- 
Once bitten, twice cry...