On Monday, 7 July 2014 at 16:58:51 UTC, anonymous wrote:
No array is created in the example. Where do you think an array
is created?
It's in the example above :
SortedRange!(MyObject[]) opSlice() {
sequence[].array.assumeSorted; }
I thought that that using ".array" would lead to instantiating
something.
Oh, must be a restriction that's going to be lifted in 2.066.
I'm using git head, so I didn't realize that it doesn't work in
2.065.
OK that's what I was suspecting... Thanks for checking that.
Looks like you can't get binary search through
SortedRange over a Range of a RedBlackTree. If you don't need
that, you can just drop SortedRange (and assumeSorted) and use
InputRange directly.
Yes it seems this is the way to go in my case.
As far as I know, true (efficient) random access on a RB tree is
not a "natural" thing and I would nto have expected that ranges
coming from those trees would support it. However it's curious
that random access was required by SortedSet, but as far as I
understand, this constraint has been recently dropped.
RandomAccessFinite is in the same family as InputRange [...]
SortedRange is a different kind of template. The template
parameter is a range type (e.g. MyObject[] or
RedBlackTree!MyObject.Range).
Replacing the one with the other doesn't make sense, and doesn't
work.
Of course ! I'm sorry I retyped it incorrectly, I tested so many
things... The actual code was the following, which seems to make
sense if SortedRange expects random access:
SortedRange!(RandomAccessFinite!MyObject) opSlice();
But then I have this error on assumeSorted() :
template std.range.assumeSorted cannot deduce function from
argument types !()(InputRange!int), candidates are: [...]
[...] Now, if you'd want to go the static-duck-typing route,
you'd
ditch the MyObjectSet interface. Instead, you'd pass
RedBlackTree!MyObject or just RedBlackTree around as a template
argument, possibly implicitly. Maybe you could give an example
of how you would use MyObjectSet. Then we could think about a
template-based alternative.
For various reasons I'm very attached to interface-oriented
design, and although I understand that this is not very "D"-like,
I'll try a little bit more in this way ;) I really like the D
language itself but for me it's almost mandatory to manipulate
abstract interface such as "ordered set" and then to be able to
switch easily between particular implementations.
Note that `sequence` is declared as RedBlackTree!MyObject, not
just RedBlackTree. There is no RedBlackTree.Range, but there is
RedBlackTree!MyObject.Range.
Yes, of course, stupid question, sorry...
Thank you very much for your help !!
Best regards,
Frédérik
