On Friday, 20 September 2013 at 14:49:21 UTC, H. S. Teoh wrote:
snip
[...]
Some trees do, like document trees. But yeah, in general, you
don't have
a natural ordering to trees.
But then again, the whole point of ranges is *linear*
traversal. If
you're not doing that, then it's probably the wrong abstraction
to use.
(FWIW, while SortedRange is a neat hack, I haven't actually
found it
that useful in practice. Most of the ranges I actually use are
for the
cases where it's an input/forward range and you don't want to
store the
whole thing, so random access is impractical. The cases where I
actually
have random access usually turn out to be plain ole arrays
anyway, so
the SortedRange abstraction isn't really necessary.)
So for trees, I'd argue that you need a tree-specific iteration
abstraction, not ranges, which are linear. It's a clear case of
structure conflict. ;-)
T
Excuse my lack of knowledge on Ranges, so maybe what I am
proposing is infeasible, for a binary tree for example couldn't
you have a InOrderRange, PreOrderRange, and PostOrderRange or
alternately DepthFirstRange, and BreadFirstRange. From a
consumers view those would be linear operations?
Craig
