This is more complex than it could be if ExtensionDecl and NominalTypeDecl
had a common ancestor in the Decl hierarchy, however this is not possible
right now because TypeDecl inherits from ValueDecl.
Fixes <rdar://problem/20981254>.
Swift SVN r28941
This allows @objc enum error types produced in Objective-C (e.g., via
+[NSError errorWithDomain:code:userInfo:]) to be bridged back to their
original enum types in Swift via pattern matching/catch blocks.
This finishes rdar://problem/20577517.
Swift SVN r28803
Inference of type witnesses for associated types was previously
implemented as part of value witness matching in the constraint
solver. This led to a number of serious problems, including:
- Recursion problems with the solver hunting for a type witness,
which triggers more attemts to match value witnesses...
- Arbitrarily crummy attempts to break the recursion causing
type-check failures in fun places.
- Ordering dependencies abound: different results depending on which
value witnesses were satisfied first, failures because of the order
in which we attempted to infer type witnesses, etc.
This new implementation of type witness inference uses a separate pass
that occurs whenever we're looking for any type witness, and solves
all of the type witnesses within a given conformance
simultaneously. We still look at potential value witnesses to infer
type witnesses, but we match them structurally, without invoking the
constraint solver.
There are a few caveats to this implementation:
* We're not currently able to infer type witnesses from value
witnesses that are global operators, so some tricks involving global
operators (*cough* ~> *cough*) might require some manually-specified
type witnesses. Note that the standard library doesn't include any
such cases.
* Yes, it's another kind of solver. At simple one, fortunately.
On the other hand, this implementation should be a big step forward:
* It's far more predictable, order-invariant, and non-recursive.
* The diagnostics for failures to infer type witnesses have
improved.
Fixes rdar://problem/20598513.
Swift SVN r27616
Provide compiler-synthesized implementations of ErrorType that use the type name as domain and a per-case integer as code. (TBD would be some mapping of the associated data to userInfo in Cocoa.)
Swift SVN r26780
The use of ASTContext-allocated arrays to store the members of nominal
type declarations and the extensions thereof is an
abomination. Instead, introduce the notion of an "iterable"
declaration context, which keeps track of the declarations within that
context (stored as a singly-linked list) and allows iteration over
them. When a member is added, it will also make sure that the member
goes into the lookup table for its context immediately.
This eliminates a ton of wasted memory when we have to reallocate the
members arrays for types and extensions, and moves us toward a much
more sane model. The only functionality change here is that the Clang
importer no longer puts subscript declarations into the wrong class,
nor does it nested a C struct within another C struct.
Swift SVN r16572
If an enum has no cases with payloads, make it implicitly Equatable and Hashable, and derive default implementations of '==' and 'hashValue'. Insert the derived '==' into module context wrapped in a new DerivedFileUnit kind, and arrange for it to be codegenned with the deriving EnumDecl by adding a 'DerivedOperatorDecls' array to NominalTypeDecls that gets visited at SILGen time.
Swift SVN r14471
For derivable protocols, such as RawRepresentable on raw-typed enums, when checking the conformance, create a conforming decl if an explicit decl wasn't found. Refactor the conformance derivation for toRaw/fromRaw to be driven by conformance checking in this way.
Swift SVN r8930
If an enum has a valid raw type, synthesize a RawType associated type along with fromRaw and toRaw methods.
An implicit conformance to RawRepresentable is not yet set up. This synthesis may need to be done earlier in order for the names to be available during type-checking of definitions in the enum too.
Swift SVN r8890
