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
We now provide fixits for if-expressions, point out the actual conditional expression (as opposed to the surrounding expression),
support unary '!' applications and avoid printing type variables in the diagnostic.
Swift SVN r20992
A checked cast such as "x as String" or "x as? [String]", where x is of
class or Objective-C existential type, is now handled as a normal
checked cast rather than a Sema-generated call to the corresponding
witness. This eliminates a pile of hairy code from constraint
application and takes a step toward <rdar://problem/17408934>.
The part of the switch_objc.swift test I removed wasn't testing
anything useful; that's what <rdar://problem/17408934> is about.
Swift SVN r20970
This is essentially NFC, but the protocols we were calling into are
changing in a way that makes it hard to use the witnesses directly
from the type checker.
Swift SVN r20933
In buildSubscript, when forcing an implicitly unwrapped optional base expression of a subscript expression, we weren't updating the base type in for later use. In the case of a nested subscript expression, this could cause us to coerce to the wrong inner type.
Swift SVN r20736
Squash _[Conditionally]BridgedToObjectiveC into one protocol. This
change results in simpler bridging code with fewer dynamic protocol
conformance checks, and solves the nasty naming/semantics problem that
resulted from having _ConditionallyBridgedToObjectiveC refining
_BridgedToObjectiveC.
Also, rename things so they're more symmetrical and less confusing.
Swift SVN r20664
To limit user confusion when using conditional expressions of type Bool?, we've decided to remove the BooleanType (aka "LogicValue") conformance from optional types. (If users would like to use an expression of type Bool? as a conditional, they'll need to check against nil.)
Note: This change effectively regresses the "case is" pattern over types, since it currently demands a BooleanType conformance. I've filed rdar://problem/17791533 to track reinstating it if necessary.
Swift SVN r20637
When a non-final class satisfies a method requirement that returns
Self, it must do so with a method that also returns (dynamic)
Self. This ensures conformance will be inheritable, closing off an
awful type-safety hole <rdar://problem/16880016>. Other
non-contravariant uses of Self in the signatures of requirements cause
the protocol to be unusable by non-final classes.
I had to leave a tiny little gaping hole for the ~> operator, whose
removal is covered by <rdar://problem/17828741>. We can possibly put
this on firm footing with clever handling of generic witnesses, but
it's not important right now.
Swift SVN r20626
When -enable-optional-lvalues is active, type-check '?' operations like '!' operations, using an OptionalObject constraint to match the optional subexpression type to the non-optional result type of equivalent lvalue-ness.
Swift SVN r20610
Previously, we were just storing setter accessibility via the accessibility
level on the setter function. However, some Stored properties never actually
have a setter synthesized, which led to the compiler dropping the setter
accessibility at serialization time. Rather than try to hack up something
clever, just store the setter accessibility explicitly in every
AbstractStorageDecl. (We still only serialize it for VarDecls, because
settable SubscriptDecls always have setter functions.)
<rdar://problem/17816530>
Swift SVN r20598
Expose Substitution's archetype, replacement, and conformances only through getters so we can actually assert invariants about them. To start, require replacement types to be materializable in order to catch cases where the type-checker tries to bind type variables to lvalue or inout types, and require the conformance array to match the number of protocol conformances required by the archetype. This exposes some latent bugs in the test suite I've marked as failures for now:
- test/Constraints/overload.swift was quietly suffering from <rdar://problem/17507421>, but we didn't notice because we never tried to codegen it.
- test/SIL/Parser/array_roundtrip.swift doesn't correctly roundtrip substitutions, which I filed as <rdar://problem/17781140>.
Swift SVN r20418
I'll reuse the EnableOptionalLValues option to stage in work on lvalue support for '?' and AnyObject lookup, but remove the conditionals on '!'.
Swift SVN r20270
Create a new "OptionalObject" constraint kind in the solver that relates an optional type to its payload type, preserving lvalue-ness, and use it to model ForceValueExpr under the optional-lvalues regime.
Swift SVN r20140
enforce its own little constraints. The type checker isn't using it for
anything, and it is just clutter.
This resolves <rdar://problem/16656024> Remove @assignment from operator implementations
Swift SVN r19960
Mechanically add "Type" to the end of any protocol names that don't end
in "Type," "ible," or "able." Also, drop "Type" from the end of any
associated type names, except for those of the *LiteralConvertible
protocols.
There are obvious improvements to make in some of these names, which can
be handled with separate commits.
Fixes <rdar://problem/17165920> Protocols `Integer` etc should get
uglier names.
Swift SVN r19883
It looks like the code for generating optional-to-optional conversions may still have problems with nested optional subtype conversions, but I don't think the application phase is the right place to address them. To holistically address this class of problem, we may want to reconsider how these kinds of optional conversions are threaded through the constraint solver post-1.0.
Swift SVN r19731
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
Previously, bridged value types and their corresponding Objective-C
classes allow inter-conversion via a number of user-defined conversion
functions in the Foundation module. Instead, make this a general
feature of the type checker so we can reason about it more
directly. Fixes <rdar://problem/16956098> and
<rdar://problem/17134986>, and eliminates 11 (half) of the
__conversion functions from the standard library and overlays.
A few notes:
- The XCTest changes are because a String can no longer directly
conform to CVarArg: this is a Good Thing (TM), because it should be
ambiguous: did you mean to pass it as an NSString or a C string?
- The Objective-C representations for the bridged collections are
hard-coded in the type checker. This is unfortunate and can be
remedied by adding another associated type to the
_BridgedToObjectiveC protocol.
Swift SVN r19618
If the lookup was resolved by optional unwrapping, unwrap the metatype when we apply the solution so we don't try to create an invalid metatype conversion from T?.Type to T.Type. Fixes <rdar://problem/17542185>.
Swift SVN r19500
When we see a '.member' expression in optional context, look for the member in the optional's object type if it isn't found in Optional itself. <rdar://problem/16125392>
Swift SVN r19469
Allow a String value to be implicitly converted to ConstUnsafePointer<{UInt8,Int8,Void}> by string-to-pointer conversion, when enabled by a staging flag.
Swift SVN r19366
JoeP helped tweak things to ensure that pointer conversions are still
considered, but we no longer need the disjunction on InOutExprs to accommodate
user-defined inout conversions.
This causes some regressions in error reporting:
<rdar://problem/17489983> inout type mismatches complain about '@lvalue inout T'
<rdar://problem/17489894> inout not rejected as operand to assignment operator
Swift SVN r19306
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
We haven't been advertising this syntax much, and it's closure form
was completely broken anyway, so don't jump through hoops to provide
great Fix-Its here.
Swift SVN r19277
Previously, we were unable to handle bridged downcasts to optional
types from optional sources, because because we applied the bridging
operation after we had already evaluated all of the bound optionals
(causing a crash). Now, we perform the bridging immediately after the
underlying forced or conditional cast, before evaluating the outer
bound optionals.
This also eliminates a bunch of code duplication between the forced
and conditional downcasts, now that the bridging code is shared.
Swift SVN r19065
Previously, a forced downcast was implemented as a conditional
downcast following by an implicit unwrap, and relied on peephole
optimizations (in both constraint application and SILGen) to turn them
into a forced downcast. However, these didn't kick in for AnyObject ->
T[] downcasts, bypassing the more-efficient deferred checking our
native collections can do. Finishes <rdar://problem/17319154>.
Swift SVN r19064
Now that we use bridgeFromObjectiveCConditional to perform conditional
bridging, make bridgeFromObjectiveC handle forced bridging. For the
latter, deferred checking is acceptable.
Almost all of <rdar://problem/17319154>.
Swift SVN r19046
These changes prevent a certain class of bogus errors, as well as several crashers. Unfortunately, though, they don't quite get us to the point where we can broadly use recursively defined protocol requirements, in the standard library. (To do so would require significant changes across the entire stack.)
Swift SVN r19019
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