A dereference iterator is used to map a pointer-like object to the
pointee, as an example given a `vector<unique_ptr<int>> Vector`, using
`dereferenceRange(Vector)` will present a range of `int &` rather than a
range of `unique_ptr<int> &`.
mapToValueIterator can be used on a map range
to access the underlying object directly rather
than the pair<key, object>.
Before this commit `is_specialization<const X<T>, X>` was not
specialized, so that `const X<T>` did not count as a specialization of
`X`. This resulted in bad selection of template specialization based on
concepts that were using `is_specialization_v`, such as
`IsUpcastablePointer`.
This commit fixes the problem, so that now the concept
`IsUpcastablePointer` is true for `const UpcastablePointer<T>` as well.
This also enabled to remove some workarounds for the `IsMutableSet` and
`IsSortedVector` concepts, and treat them uniformly with other concepts
that were using `is_specialization_v`.
This commit:
* Drops `KeyTraits::toString`: if needed, use `getNameFromYAMLScalar`.
* Makes many methods in TupleTree.h return `nullptr` or `std::optional`
in order to gracefully handle failures.
* Provides `KeyTraits` specializations for integral types and tuple-like
composed by types providing `KeyTraits`.
* Introduces `CompositeScalar`, which enables tuple-like objects to be
YAML-serializable scalars by joining the YAML-serialization of its
members through a customziable character.
* Implements `PathMatcher`, a very simple "regular expression" mechanism
for paths on tuple trees.
* Introduce testing for the Model.
These data structures are substitutes for a `std::map<Key, Value>` where
`Key` is embedded in `Value`. Their main goal is to be serializable in a
YAML sequence while preserving the order enforced by the key.
`MutableSet` is implemented using a map.
`SortedVector` is implemented using a sorted vector.
Ivan Krysak