Rebindable2 did not handle types with opAssign correctly, which affected
both minElement and maxElement. Namely, Rebindable2 assigned to memory
which was not properly initialized when the correct solution in such a
situation is to use copyEmplace. Assignment works when assignment is
just a memcpy, but in the general case, opAssign needs to have a
properly initialized object in order to work correctly. copyEmplace
instead copies the object and then places the copy into the unitialized
memory, so it avoids assigning to uninitialized memory.
This commit also adds additional tests for types with destructors (which
do get opAssign automatically) and types with postblit constructors or
copy constructors to try to ensure that the code is doing the correct
thing in those cases with regards to copying, assignment, and
destruction.
https://issues.dlang.org/show_bug.cgi?id=24829 was found in the process,
and this does not fix that. Namely, types which cannot be assigned to
and which also have a postblit constructor or copy constructor do not
get copied correctly. So, among the tests added here are commented out
tests for that case, since they're an altered version of some of the
enabled tests. However, fixing that issue would be involved enough that
I'm not attempting to fix it at this time.
Fix `value` missing reference.
Tweak wording.
Explain `pred` better.
Separate out needle overloads from the other 2.
Fix 'Returns'.
Split example into 2.
`until` does special magic when `Sentinel` consists of multiple elements of `Range`. However, because `Range` can be a range of ranges, in which case even a `Sentinel` that is a range may still only be a single element, we must confirm that the element type of `Sentinel` is actually the same as `Range` before enabling this.
The `immutable ElementEncodingType` idiom is stolen from `startsWith`, which forms the basis of `until` anyways (see `predSatisfied`).
It's much clearer to have separate docs for the overload not taking
`needle`, because its `pred` has a different signature and its behaviour
is simpler. It was necessary to move that overload (and its unittests)
above the other two.
Also improve the docs for the other overloads:
Remove duplicate BIGOH sentence already present under *Complexity*.
Use `e, n` for predicate parameter names, short for `element, needle`.
The requirement that each needle must be a range is arbitrary, so remove
it.
Note: This overload of `canFind` calls `find(haystack, needles)` which
calls `startsWith`, which accepts mixed element and range needles.
Rebindable2 is a simplified version of std.typecons.Rebindable that clears up every special case: classes, arrays and structs now have the same struct.
Whichever type you instantiate `Rebindable2` with, you always get the same type out by calling `value.get` on the resulting container.
Also use this type to simplify the parts of Phobos we previously used `Rebindable` for.
