• =?UTF-8?B?Tm9yZGzDtnc=?= (9/9) Nov 02 2016 Does
• =?UTF-8?B?Tm9yZGzDtnc=?= (7/9) Nov 02 2016 A typical use case is intersection of the two sets `x` and `y`.
• Andrei Alexandrescu (4/11) Nov 02 2016 Currently we don't have a good framework for associative ranges yet. We

=?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:

Does

https://dlang.org/phobos/std_algorithm_setops.html

support specializations when (some) arguments are 
containers/ranges that provide the `in` operator?

Typically set- and map-like containers with O(1) key membership 
checking.

If not, should they?

And what about operator overloading for union (|), intersection 
(&) and difference (-)?

=?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:

On Wednesday, 2 November 2016 at 13:45:41 UTC, Nordlöw wrote:
 Typically set- and map-like containers with O(1) key membership 
 checking.

A typical use case is intersection of the two sets `x` and `y`.

When `x` and `y` both support O(1)-`contains(e)` the preferred 
algorithm is to interate over all elements in the shorter 
(smallest .length) of `x` and `y` (called `s`), and return only 
those elements of type E in `s` than can be looked up in `l` via 
`l.contains(E)`.

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 11/02/2016 11:07 AM, Nordlöw wrote:
 On Wednesday, 2 November 2016 at 13:45:41 UTC, Nordlöw wrote:
 Typically set- and map-like containers with O(1) key membership checking.

 A typical use case is intersection of the two sets `x` and `y`.

 When `x` and `y` both support O(1)-`contains(e)` the preferred algorithm
 is to interate over all elements in the shorter (smallest .length) of
 `x` and `y` (called `s`), and return only those elements of type E in
 `s` than can be looked up in `l` via `l.contains(E)`.

Currently we don't have a good framework for associative ranges yet. We 
should define what the associative operations are, and then we can 
proceed to see where they'd make sense. -- Andrei