This commit is a potentially breaking change, but the problem was that
linalg was relying on a previous bug in the compiler, which was fixed
in the concepts branch.
With the old disambiguation rules, generic procs like:
proc \`==\`[T](lhs, rhs: T)
and
proc \`==\`(lhs, rhs: Matrix32|Matrix64)
.. were considered equal, even though it's obvious that the second one
should be preferred. We never noticed this, because there was a bug in
sigmatch incorrectly counting one of the params of the second proc as
a non-generic match, thus giving it an edge.
This commit gives some preference to tyOr and tyAnd during the complex
disambiguation, which may affect overload resolution in other cases.
I see this only as a temporary solution. With my upcoming work on
concept refinement, I plan to provide an experimental implementation
of alaternative C++-like rules for determining which proc is more specific.
We can then discuss our strategy for dealing with such a breaking change.
A more efficient implementation is possible by restoring the old
lifting ot tyGenericInvocation to tyGenericInst in liftTypeParam,
but this fix will suffice for now.
fixes#5087fixes#5602fixes#5641fixes#5570
This implements a number of new safety checks and error messages
when object constructors are used:
In case objects:
* the compiler will prevent you from initializing fields in
conflicting branches
* When a field from a particular branch is initialized, the
compiler will demand that the discriminator field is also
supplied with a maching compile-time value
In all objects:
* When the "requiresInit" pragma is applied to a type, all fields
of the type must be initialized when object construction is used.
The code will be simplified in a follow up commit.
