static bool canSynthesizeRawRepresentable(TypeChecker &tc, Decl *parentDecl,
EnumDecl *enumDecl) {
// Validate the enum and its raw type.
tc.validateDecl(enumDecl);
// It must have a valid raw type.
Type rawType = enumDecl->getRawType();
if (!rawType)
return false;
auto parentDC = cast<DeclContext>(parentDecl);
rawType = parentDC->mapTypeIntoContext(rawType);
auto inherited = enumDecl->getInherited();
if (!inherited.empty() && inherited.front().wasValidated() &&
inherited.front().isError())
return false;
// The raw type must be Equatable, so that we have a suitable ~= for
// synthesized switch statements.
auto equatableProto = tc.getProtocol(enumDecl->getLoc(),
KnownProtocolKind::Equatable);
if (!equatableProto)
return false;
if (!tc.conformsToProtocol(rawType, equatableProto, enumDecl, None))
return false;
// There must be enum elements.
if (enumDecl->getAllElements().empty())
return false;
// Have the type-checker validate that:
// - the enum elements all have the same type
// - they all match the enum type
for (auto elt : enumDecl->getAllElements()) {
tc.validateDecl(elt);
if (elt->isInvalid()) {
return false;
}
}
// If it meets all of those requirements, we can synthesize RawRepresentable conformance.
return true;
}
static bool canSynthesizeRawRepresentable(TypeChecker &tc, Decl *parentDecl, EnumDecl *enumDecl) {
// It must have a valid raw type.
Type rawType = enumDecl->getRawType();
if (!rawType)
return false;
auto parentDC = cast<DeclContext>(parentDecl);
rawType = ArchetypeBuilder::mapTypeIntoContext(parentDC, rawType);
if (!enumDecl->getInherited().empty() &&
enumDecl->getInherited().front().isError())
return false;
// The raw type must be Equatable, so that we have a suitable ~= for synthesized switch statements.
auto equatableProto = tc.getProtocol(enumDecl->getLoc(),
KnownProtocolKind::Equatable);
if (!equatableProto)
return false;
if (!tc.conformsToProtocol(rawType, equatableProto, enumDecl, None)) {
SourceLoc loc = enumDecl->getInherited()[0].getSourceRange().Start;
tc.diagnose(loc, diag::enum_raw_type_not_equatable, rawType);
return false;
}
// There must be enum elements.
if (enumDecl->getAllElements().empty())
return false;
// Have the type-checker validate that:
// - the enum elements all have the same type
// - they all match the enum type
for (auto elt : enumDecl->getAllElements()) {
tc.validateDecl(elt);
if (elt->isInvalid()) {
return false;
}
}
// If it meets all of those requirements, we can synthesize RawRepresentable conformance.
return true;
}
