There are a lot of different ways to interpret the
"kind" of an access. This enum specifically dictates
the semantic rules for an access: direct-to-storage
and direct-to-accessor accesses may be semantically
different from ordinary accesses, e.g. if there are
observers or overrides.
Swift SVN r22290
This patch adds the ability (-enable-experimental-unavailable-as-optional) to
treat potentially unavailable declarations as if they had optional types. For
the moment, this is only implemented for global variables.
The high-level approach is to (1) record the potential unavailability of a
declaration reference in the overload choice during constraint generation; (2)
treat the declaration as if it had an optional type during overload resolution
(this is similar to how optional protocol members are treated); and (3) add an
implicit conversion (UnavailableToOptionalExpr) during constraint application
to represent the run-time availability check and optional injection.
This patch does not implement SILGen for UnavailableToOptionalExpr.
Swift SVN r22245
This patch extends the AST and parsing of #os(...) queries to permit queries for
multiple platforms, e.g., #os(OSX >= 10.10, iOS >= 8.0). It also improves
parsing error recovery.
Swift SVN r22154
This commit adds a new expression (AvailabilityQueryExpr) and a single kind of
specification for when a block of code or function is available
(VersionConstraintAvailabilitySpec). We may add more kinds of specifications
in the future. At the moment, the AvailabilityQueryExpr allows only a
single platform to be queried; I will add support for multiple platforms
in a later commit.
This commit contains just the added AST nodes; no parsing, type checking, etc.
I’ve added assert(false && “Unimplemented”) for places where support for
AvailabilityQueryExpr will need to be added later.
Swift SVN r21760
Introduce an attribute that describes when a given CF type is
toll-free-bridged to an Objective-C class, and which class that
is. Use that information in the type checker to provide the CF <->
Objective-C toll-free-bridged conversions directly, rather than using
the user-defined conversion machinery.
Swift SVN r21376
This allows UnicodeScalars to be constructed from an integer, rather
then from a string. Not only this avoids an unnecessary memory
allocation (!) when creating a UnicodeScalar, this also allows the
compiler to statically check that the string contains a single scalar
value (in the same way the compiler checks that Character contains only
a single extended grapheme cluster).
rdar://17966622
Swift SVN r21198
Introduce the new BooleanLiteralConvertible protocol for Boolean
literals. Take "true" and "false" as real keywords (which is most of the
reason for the testsuite churn). Make Bool BooleanLiteralConvertible
and the default Boolean literal type, and ObjCBool
BooleanLiteralConvertible. Fixes <rdar://problem/17405310> and the
recent regression that made ObjCBool not work with true/false.
Swift SVN r19728
This always wrapped a single GenericTypeParamDecl *, and provided no benefit
over just using the decl directly.
No (intended) functionality change.
Swift SVN r19628
We no longer need this language feature. The Sema support is still skeletally kept in place because removing it seems to totally break pointer conversions; I need to work with Joe and Doug to figure out why that's the case.
Swift SVN r19289
Handle parsing of dictionary type sugar into its own type
representation, including both type and expression contexts.
This is the first part of <rdar://problem/17460972>; we still need a
sugared Type node.
Swift SVN r19239
When checking an isa pattern that requires either collection
downcasting or bridging through an Objective-C class (e.g.,
"is String" or "is Dictionary<String, Int>"), form a conditional
downcast and place it in an expression pattern.
With this change, we can test for these cases (with "is") but we can't
capture the value produced on success (e.g., for "let str as
String"). This is a first small step toward <rdar://problem/17408934>.
Swift SVN r19070
Add primitive type-checker rules for pointer arguments. An UnsafePointer argument accepts:
- an UnsafePointer value of matching element type, or of any type if the argument is UnsafePointer<Void>,
- an inout parameter of matching element type, or of any type if the argument is UnsafePointer<Void>, or
- an inout Array parameter of matching element type, or of any type if the argument is UnsafePointer<Void>.
A ConstUnsafePointer argument accepts:
- an UnsafePointer, ConstUnsafePointer, or AutoreleasingUnsafePointer value of matching element type, or of any type if the argument is ConstUnsafePointer<Void>,
- an inout parameter of matching element type, or of any type if the argument is ConstUnsafePointer<Void>, or
- an inout or non-inout Array parameter of matching element type, or of any type if the argument is ConstUnsafePointer<Void>.
An AutoreleasingUnsafePointer argument accepts:
- an AutoreleasingUnsafePointer value of matching element type, or
- an inout parameter of matching element type.
This disrupts some error messages in unrelated tests, which is tracked by <rdar://problem/17380520>.
Swift SVN r19008
This means that we'll get deferred checking of array and dictionary
downcasts when writing "arr as Derived[]",
"(dict as? Dictionary<DerivedKey, DerivedValue>)!", etc, when the
collection can do so.
This is both a general optimization and also staging for
<rdar://problem/17319154>.
Swift SVN r18975
This is all goodness, and eliminates a major source of implicit conversions.
One thing this regresses on though, is that we now reject "x == nil" where
x is an option type and the element of the optional is not Equtatable. If
this is important, there are ways to enable this, but directly testing it as
a logic value is more straight-forward.
This does not include support for pattern matching against nil, that will be
a follow on patch.
Swift SVN r18918
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
