Semantically, these expressions handle the same thing: an upcast of a
collection when the underlying element types of the source are
subtypes of or can be bridged to subtypes of the destination. This
reduces some branching in the type checker and eliminates duplication
in SILGen.
Swift SVN r18865
Allow class metatypes (including class-constrained existential metatypes) to be treated as subtypes of AnyObject, and single-@objc protocol metatypes to be treated as subtypes of the Protocol class from objc. No codegen support yet, so this is hidden behind a frontend flag for now.
Swift SVN r18810
There's a bit of a reshuffle of the ExplicitCastExpr subclasses:
- The existing ConditionalCheckedCastExpr expression node now represents
"as?".
- A new ForcedCheckedCastExpr node represents "as" when it is a
downcast.
- CoerceExpr represents "as" when it is a coercion.
- A new UnresolvedCheckedCastExpr node describes "as" before it has
been type-checked down to ForcedCheckedCastExpr or CoerceExpr. This
wasn't a strictly necessary change, but it helps us detangle what's
going on.
There are a few new diagnostics to help users avoid getting bitten by
as/as? mistakes:
- Custom errors when a forced downcast (as) is used as the operand
of postfix '!' or '?', with Fix-Its to remove the '!' or make the
downcast conditional (with as?), respectively.
- A warning when a forced downcast is injected into an optional,
with a suggestion to use a conditional downcast.
- A new error when the postfix '!' is used for a contextual
downcast, with a Fix-It to replace it with "as T" with the
contextual type T.
Lots of test updates, none of which felt like regressions. The new
tests are in test/expr/cast/optionals.swift.
Addresses <rdar://problem/17000058>
Swift SVN r18556
Array downcast is an explicit cast written "x as U[]", not an implicit
conversion, so make it a subclass of ExplicitCastExpr. The only
effective change here is that we retain the location of the "as" and
the type as written in the AST. No semantic change.
Swift SVN r18391
- Continue adding support for checked downcasts of array types (rdar://problem/16535104)
- Fix non-bridged array conversions post-r17868
- Fix rdar://problem/16773693
- Add tests for NSArray coercions to and from Array<T>
Swift SVN r17957
storage can be explicitly specified with a memberwise constructor (this already
worked) and the presence of the property shouldn't block synth of the default
ctor since it is default initialized to nil.
Unrelatedly, print the lazy attribute in the AST dumper.
Swift SVN r17925
PatternBindingDecls, and inject the vardecls into the name resolution
scope while parsing the body of the closure. This allows references
from the body of the closure to be resolved to the capture list,
e.g. in cases like the testcase.
Swift SVN r17760
- Change astdumper to print the typerepr in the more canonical syntax.
- Remove bogus logic from CSApply that was preventing us from rewriting
TypeExprs properly
- Teach CSGen to handle unbound generics correctly (thanks to Doug for the help on this)
Swift SVN r17007
This restructures IfConfigDecl/Stmt to be a list of clauses controlled
by a condition. This makes it straight-forward to drop in #elseif support.
While I'm in here, this patch moves checking for extraneous stuff at the
end of the #if line from the lexer to the parser. This means that you can
now put a comment on the same line as a #if/#else/#elseif/#endif.
Swift SVN r16912
them with uses of TypeExpr instead. The remaining uses of
MetaTypeExpr (which will be renamed soon) are places where we
are applying the ".dynamicType" virtual property to an expression.
Unadorned uses of types in code, e.g. the Int in "Int.self" are
now represented with TypeExpr.
One unfortunate travesty that doing this work revealed is that we
are extremely sloppy and terrible about maintaining location information
in implicitly generated decls, and our invariants vary quite a bit. This
is really horrible, but I'm not sure whether I'll go fix the hacks or not.
This patch perpetuates the existing crimes, but makes them more visible.
NFC!
Swift SVN r16646
when resolving identifiers into types. This will eventually allow us to
solve annoying issues like rdar://15295763&15588967 by better modeling
what we already have.
Swift SVN r16620
Use this node to capture the argument name and its source location in
the AST. We're only building these in one place at the moment; the
rest will be updated soon.
Swift SVN r16581
Factory initializers express an initializer that produces an object of
the given type, but is not inherited and not designated. Although they
have a syntactic form for presentation purposes (-> ClassName), there
is no way to specify or implement them within Swift. Rather, factory
initializers are created when importing an Objective-C factory method
that returns the class type rather than instancetype.
Swift SVN r16528
Convenience factory initializers are convenience initializers produced
by importing an Objective-C factory method as a convenience
initializer. The distinction is currently only used to eliminate the
awful layering violation I recently introduced in name lookup, which
was consulting Clang AST nodes directly. It will also be useful in
SILGen.
Swift SVN r16527
Introduce CtorInitializerKind to describe the kind of an enum, rather
than a bool, to make way for more initializer kinds in the future.
Swift SVN r16525
Teach SILGen to handle function representation changes as part of function conversion instead of needing to be spoonfed a special expr for the purpose. Handle representation changes in both directions to and from blocks using the same logic as the bridging conversions.
Swift SVN r16318
Add a third branch to the constraint system for '&x' expressions that allows conversion from an lvalue to a type via an additional writeback step:
- Add an LValueConversionExpr node that converts from @lvalue T to @lvalue U, given a pair of functions that convert T -> U and U -> T, to represent the writeback temporary.
- Allow conversion in an inout expression from @lvalue T to a type U that has the following members:
static func __writeback_conversion(Builtin.RawPointer, T.Type) -> U
static func __writeback_conversion_get(T) -> V
static func __writeback_conversion_set(V) -> T
which builds a solution that produces an LValueConversion from the get/set pair before passing the pointer to the writeback temporary off to the conversion function.
Swift SVN r15764
Add two new AST node types:
- InOutConversionExpr, which represents an '&x' expression that involves inout conversion. This will be a signal to SILGen not to introduce a writeback scope for the nested conversion call.
- LValueToPointerExpr, which represents the primitive '@lvalue T' to 'RawPointer' conversion that produces the argument to the inout conversion.
Build an InOutConversionExpr AST when an inout expression is resolved by a conversion to an BuiltinInOutAddressConvertible type.
Swift SVN r15594
Allow a form of 'case is T' that matches the cast result to a subpattern, 'case <pattern> as T'. This exposes an issue in switch destructuring with casting into complex class hierarchies <rdar://problem/16401831> but works for common cases.
Swift SVN r15396
