UnresolvedConstructorExpr is not providing any value here; it's
essentially just UnresolvedDotExpr where the name refers to an
initializer, so use that instead. NFC
mode (take 2)
Allow untyped placeholder to take arbitrary type, but default to Void.
Add _undefined<T>() function, which is like fatalError() but has
arbitrary return type. In playground mode, merely warn about outstanding
placeholders instead of erroring out, and transform placeholders into
calls to _undefined(). This way, code with outstanding placeholders will
only crash when it attempts to evaluate such placeholders.
When generating constraints for an iterated sequence of type T, emit
T convertible to $T1
$T1 conforms to SequenceType
instead of
T convertible to SequenceType
This ensures that an untyped placeholder in for-each sequence position
doesn't get inferred to have type SequenceType. (The conversion is still
necessary because the sequence may have IUO type.) The new constraint
system precipitates changes in CSSimplify and CSDiag, and ends up fixing
18741539 along the way.
(NOTE: There is a small regression in diagnosis of issues like the
following:
class C {}
class D: C {}
func f(a: [C]!) { for _: D in a {} }
It complains that [C]! doesn't conform to SequenceType when it should be
complaining that C is not convertible to D.)
<rdar://problem/21167372>
(Originally Swift SVN r31481)
Allow untyped placeholder to take arbitrary type, but default to Void.
Add _undefined<T>() function, which is like fatalError() but has
arbitrary return type. In playground mode, merely warn about outstanding
placeholders instead of erroring out, and transform placeholders into
calls to _undefined(). This way, code with outstanding placeholders will
only crash when it attempts to evaluate such placeholders.
<rdar://problem/21167372> transform EditorPlaceholderExpr into fatalError()
Swift SVN r31481
conversions to and from UnresolvedType. This will allow UnresolvedType to be
used more aggressively and predictably by CSDiags. This is NFC, but used in
the next patch.
Swift SVN r31318
This is a step towards partially-applying methods that return Self
on existentials.
- We model opening of both existential values and metatypes with
OpenExistentialExpr, but erasure had two forms, ErasureExpr and
MetatypeErasureExpr. Combine them into one, since both Sema and
SILGen have similar code paths for each.
- If the source type of an ErasureExpr is a closed existential,
have Sema emit an OpenExistentialExpr, and remove SILGen's
openExistentialForErasure() path, which mostly duplicates
openExistentialImpl().
- There was one difference between openExistentialForErasure() and
openExistentialImpl(). The former would emit the opaque value in
+0 context, and the latter in a +1 with initialization. The
previous patch ensures that visitOpaqueValueExpr() generates
equivalent code in both cases.
Swift SVN r31261
To support this, make 'try' and 'try!' no longer IdentityExprs
and give them a common base class to simplify the sorts of
analyses and transformations that do want to treat them
as identity-like.
Note that getSPE() still looks through normal 'try', since
the overwhelming proportion of clients will consider it
semantically equivalent to the undecorated expression.
Change getValueProvidingExpr() to look through try!, since
it's allowed to return something with slightly different
semantics, and use it in the unused-result diagnostic.
Fixes a large number of bugs, mostly uncaught, with SILGen
peepholes that use getSPE() and therefore were accidentally
looking through try!. <rdar://21515402>
Swift SVN r30224
instead of being an expression.
To the user, this has a couple of behavior changes, stemming from its non-expression-likeness.
- #available cannot be parenthesized anymore
- #available is in its own clause, not used in a 'where' clause of if/let.
Also, the implementation in the compiler is simpler and fits the model better. This
fixes:
<rdar://problem/20904820> Following a "let" condition with #available is incorrectly rejected
Swift SVN r28521
Add syntax "[#Color(...)#]" for object literals, to be used by
Playgrounds for inline color wells etc. The arguments are forwarded to
the relevant constructor (although we will probably change this soon,
since (colorLiteralRed:... blue:... green:... alpha) is kind of
verbose). Add _ColorLiteralConvertible and _ImageLiteralConvertible
protocols, and link them to the new expressions in the type checker.
CSApply replaces the object literal expressions with a call to the
appropriate protocol witness.
Swift SVN r27479
If the placeholder is a typed one, parse its type string into a TypeRepr,
resolve it during typechecking and set it as the type for the associated EditorPlaceholderExpr.
Swift SVN r26215
We parse 'try' as if it were a unary operator allowed on an
arbitrary element of an expr-sequence, but sequence-folding
constrains it to never appear on the RHS of most operators.
We do allow it on the RHS of an assignment or conditional
operator, but not if there's anything to the right which
was not parsed within the RHS.
We do this for assignments so that
var x = try whatever
and
x = try whatever
both work as you might expect.
We do this for conditionals because it feels natural to
allow 'try' in the center operand, and then disallowing it
in the right operand feels very strange.
In both case, this works largely because these operators are
assumed to be very low-precedence; there are no standard
operators which would parse outside the RHS. But if you
create one and use 'try' before it, we'll diagnose it.
Swift SVN r26052
Previously the "as" keyword could either represent coercion or or forced
downcasting. This change separates the two notions. "as" now only means
type conversion, while the new "as!" operator is used to perform forced
downcasting. If a program uses "as" where "as!" is called for, we emit a
diagnostic and fixit.
Internally, this change removes the UnresolvedCheckedCastExpr class, in
favor of directly instantiating CoerceExpr when parsing the "as"
operator, and ForcedCheckedCastExpr when parsing the "as!" operator.
Swift SVN r24253
a capture list hung off the CaptureExpr it was associated with. This made
sense lexically (since a capture list is nested inside of the closure) but
not semantically. Semantically, the capture list initializers are evaluated
outside the closure, the variables are bound to those values, then the closure
captures the newly bound values.
To directly represent this, represent captures with a new CaptureListExpr node,
which contains the ClosureExpr inside of it. This correctly models the semantic
relationship, and makes sure that AST walkers all process the initializers of the
capture list as being *outside* of the closure.
This fixes rdar://19146761 and probably others.
Swift SVN r23756
Provides consistency in behavior, particularly in enum raw values, where we reject non-literals. Factor out a common NumberLiteralExpr base for integer and float literals that handles the common sign and representation stuff. Fixes rdar://problem/16504472.
Swift SVN r23390
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 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
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
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
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
