canImport should be able to take an additional parameter labeled by either version or
underlyingVersion. We need underlyingVersion for clang modules with Swift overlays because they
have separate version numbers. The library users are usually interested in checking the importability
of the underlying clang module instead of its Swift overlay.
Part of rdar://73992299
This patch replaces the @hasAsyncAlternative attribute with
@completionHandlerAsync. The @completionHandlerAsync attribute takes the
function decl name of the async function and optionally the index of the
completion hander parameter in the function that it's attached to.
If the completion handler index is not provided, it's assumed to be the
last parameter in the parameter list.
We resolve the async function while typechecking the attribute. Before
resolving, we verify that the function the attribute is attached to
isn't async, that it has enough parameters to at least have the
indicated completion handler referenced by the index, that the
completion handler is an escaping non-auto-closure function that returns
Void.
The async function declaration resolution isn't perfect yet, but I want
to get this patch up and we can refine it later. It pulls all of the
delcs with the specified declname in the same context as the
function that the attribute is attached to. Going through that list, it
keeps any that are async functions. If there are none, we emit an error
saying that there are no viable functions, if there are multiple we emit
an error saying that the decl name is ambiguous, and if there is one
function, we keep that as the resolve async function declaration.
This does not take into account the data types of the completion handler
or the async function. There are some complexities to making this
mapping. Here are the pieces:
- If the completion handler takes a single data type, the async
function should return that type. (easy case)
- If the completion handler takes a `Result<T, Error>`, the async
function is a throwing function that returns a T. (Medium difficulty)
- If the completion handler looks like `(T?, Error?) -> Void`, we have
an ambiguous situation between the following async functions:
- func foo() async throws -> T
- func foo() async throws -> T?
That is, we cannot tell whether the `T?` in the completion handler is
optional because it will be nil on an error, or if it is intended to
be optional.
This can be done later if it becomes a problem.
This patch removes the feature flag for @hasAsyncAlternative since it's
already protected by the experimental concurrency flag and will go in
with the concurrency features.
This fixes one of Doug's comments on
https://github.com/apple/swift/pull/36027.
This attribute marks a function has having an async alternative,
optionally providing the name of that function as a string. Intended to
be used to allow warnings when using a function with an async
alternative in an asynchronous context, to make the async refactorings
more accurate, and for documentation.
Compiler:
- Add `Forward` and `Reverse` to `DifferentiabilityKind`.
- Expand `DifferentiabilityMask` in `ExtInfo` to 3 bits so that it now holds all 4 cases of `DifferentiabilityKind`.
- Parse `@differentiable(reverse)` and `@differentiable(_forward)` declaration attributes and type attributes.
- Emit a warning for `@differentiable` without `reverse`.
- Emit an error for `@differentiable(_forward)`.
- Rename `@differentiable(linear)` to `@differentiable(_linear)`.
- Make `@differentiable(reverse)` type lowering go through today's `@differentiable` code path. We will specialize it to reverse-mode in a follow-up patch.
ABI:
- Add `Forward` and `Reverse` to `FunctionMetadataDifferentiabilityKind`.
- Extend `TargetFunctionTypeFlags` by 1 bit to store the highest bit of differentiability kind (linear). Note that there is a 2-bit gap in `DifferentiabilityMask` which is reserved for `AsyncMask` and `ConcurrentMask`; `AsyncMask` is ABI-stable so we cannot change that.
_Differentiation module:
- Replace all occurrences of `@differentiable` with `@differentiable(reverse)`.
- Delete `_transpose(of:)`.
Resolves rdar://69980056.
Always parse `async` and `await`, allowing the definition and use of
asynchronous functions without the "experimental concurrency" flag.
Note that, at present, use of asynchronous functions requires one to
explicitly import or link against the `_Concurrency` library. We'll
sort this out in a follow-up change.
Tracked by rdar://73455330.
By replacing the 'async' with 'await' in the parser, we avoid the issue
of cascading errors as the compiler gets more and more confused by what
it's reading. Instead, everything mostly passes and we just emit the one
error message.
One caveat that I hadn't taken into account before was that we could
have a function called "async", in which case we don't want to replace
the "async" keyword with "await".
Protocol requirements don't support default arguments. Although this is
a "semantic" diagnostics, we currently do this for 'func' and 'init' in
Parser. So for fixing a crash, let's to it for 'subscript' in Parser
too.
rdar://problem/73159041
Availability macros passed via the frontend flag -define-availability
should be accepted by @_originallyDefinedIn where they behave as they do
in @available.
rdar://72354787
The `try await` ordering is both easier to read and indicates the order
of operations better, because the suspension point occurs first and
then one can observe a thrown error.
[broken] first impl of @actorIndependent in the type checker.
[broken] fixed mistake in my parsing code wrt invalid source range
[broken] found another spot where ActorIndependent needs custom handling
[broken] incomplete set of @actorIndependent(unsafe) tests
updates to ActorIndependentUnsafe
[fixed] add FIXME plus simple handling of IndependentUnsafe context
finished @actorIndependent(unsafe) regression tests
added wip serialization / deserialization test
focus test to just one actor class
round-trip serialize/deserialize test for @actorIndependent
serialize -> deserialize -> serialize -> compare to original
most of doug's comments
addressed robert's comments
fix printing bug; add module printing to regression test
[nfc] update comment for ActorIsolation::IndependentUnsafe
```
@_specialize(exported: true, spi: SPIGroupName, where T == Int)
public func myFunc() { }
```
The specialized entry point is only visible for modules that import
using `_spi(SPIGroupName) import ModuleDefiningMyFunc `.
rdar://64993425
This attribute allows to define a pre-specialized entry point of a
generic function in a library.
The following definition provides a pre-specialized entry point for
`genericFunc(_:)` for the parameter type `Int` that clients of the
library can call.
```
@_specialize(exported: true, where T == Int)
public func genericFunc<T>(_ t: T) { ... }
```
Pre-specializations of internal `@inlinable` functions are allowed.
```
@usableFromInline
internal struct GenericThing<T> {
@_specialize(exported: true, where T == Int)
@inlinable
internal func genericMethod(_ t: T) {
}
}
```
There is syntax to pre-specialize a method from a different module.
```
import ModuleDefiningGenericFunc
@_specialize(exported: true, target: genericFunc(_:), where T == Double)
func prespecialize_genericFunc(_ t: T) { fatalError("dont call") }
```
Specially marked extensions allow for pre-specialization of internal
methods accross module boundries (respecting `@inlinable` and
`@usableFromInline`).
```
import ModuleDefiningGenericThing
public struct Something {}
@_specializeExtension
extension GenericThing {
@_specialize(exported: true, target: genericMethod(_:), where T == Something)
func prespecialize_genericMethod(_ t: T) { fatalError("dont call") }
}
```
rdar://64993425
Introduce availability macros defined by a frontend flag.
This feature makes it possible to set the availability
versions at the moment of compilation instead of having
it hard coded in the sources. It can be used by projects
with a need to change the availability depending on the
compilation context while using the same sources.
The availability macro is defined with the `-define-availability` flag:
swift MyLib.swift -define-availability "_iOS8Aligned:macOS 10.10, iOS 8.0" ..
The macro can be used in code instead of a platform name and version:
@available(_iOS8Aligned, *)
public func foo() {}
rdar://problem/65612624
Similar to `try`, await expressions have no specific semantics of their
own except to indicate that the subexpression contains calls to `async`
functions, which are suspension points. In this design, there can be
multiple such calls within the subexpression of a given `await`.
Note that we currently use the keyword `__await` because `await` in
this position introduces grammatical ambiguities. We'll wait until
later to sort out the specific grammar we want and evaluate
source-compatibility tradeoffs. It's possible that this kind of prefix
operator isn't what we want anyway.
Add `async` to the type system. `async` can be written as part of a
function type or function declaration, following the parameter list, e.g.,
func doSomeWork() async { ... }
`async` functions are distinct from non-`async` functions and there
are no conversions amongst them. At present, `async` functions do not
*do* anything, but this commit fully supports them as a distinct kind
of function throughout:
* Parsing of `async`
* AST representation of `async` in declarations and types
* Syntactic type representation of `async`
* (De-/re-)mangling of function types involving 'async'
* Runtime type representation and reconstruction of function types
involving `async`.
* Dynamic casting restrictions for `async` function types
* (De-)serialization of `async` function types
* Disabling overriding, witness matching, and conversions with
differing `async`
* [Parser] Update 'Confusables.def' file to include confusable and base character names
* [Parser] Add a new utility method to return the names of the confusable and base characters for a given confusable codepoint
* [Parser] Update diagnostic for confusable character during lexing to mention confusable and base character names
* [Sema] If there is just a single confusable character, emit a tailored diagnostic that also mentions the character names
* [Diagnostics] Add new diagnostic messages to the localization file
* [Test] Update confusables test
* [Utils] Update unicode confusables txt file and update script to regenerate confusables def file
* [Parse] Regenerate 'Confusables.def' using updated script
* [Utils] Adjust generate_confusables script based on review feedback
Fix a mistake with name mapping. Updated header comment. Fix a couple of linting issues.
* [Parse] Regenerate 'Confusables.def' file once again after script changes
* [Parse] Add the newline after end of 'getConfusableAndBaseCodepointNames' method
* [Test] Update diagnostic message in 'Syntax/Parser/diags.swift'
These were duplicated in 11 different files, and as they've gotten more
complex a few inconsistencies have snuck in. Sharing them should make future
changes easier and less bug-prone.
The client code doesn't actually call into these specialized functions even
though they have public linkage. This could lead to TBD verification failure
shown in rdar://44777994.
This patch also warns users' codebase when `export: true` is specified.