as always, it turned out that the alledged "compiler bug"
rather was my own sloppyness: I forgot properly to undo a change
I made while fighting with compilation problems: the wrapper in
the factory didn't use std::forward, resulting in a plain flat
slicing copy. This, rightfully, triggered the assertion in the
session query resolver (since a sliced Goal can not be dynamic cast
to a specific Query subclass).
...but the whole design looks still overengineered. See #388
- should get rid of the explicit specialisation
- always use a function signature and thus have arguments?
- why inheriting from the wrapper?
still puzzled why this instantiation of MultiFact fails to compile with GCC 4.8
so I'm bound to understand why the types involved
need indeed to be are structured the way they are right now.
lib::Depend<TY> works as drop-in replacement for lib::Singleton<TY>
This changeset removes the convoluted special cases like
SingletonSub and MockInjector.
This template was a leftover from the early days
of Lumiera development and doesn't provide any
substantial value as an abstraction.
For the more intricate cases, we're using the
lib::MultiFact template, which allows to install
several "fabrication" functions at runtime
