Since type wrapper attributes could be applied to protocols and
the protocol types could be used as existential values, it's not
always possible to wrap all uses of feature into `#if $TypeWrappers`
block so let's allow use of attributes if they come from a Swift
interface file.
Align the grammar of macro declarations with SE-0382, so that macro
definitions are parsed as an expression. External macro definitions
are referenced via a referenced to the macro `#externalMacro`. Define
that macro in the standard library, and recognize uses of it as the
definition of other macros to use externally-defined macros. For
example, this means that the "stringify" macro used in a lot of
examples is now defined as something like this:
@expression macro stringify<T>(_ value: T) -> (T, String) =
#externalMacro(module: "MyMacros", type: "StringifyMacro")
We still parse the old "A.B" syntax for two reasons. First, it's
helpful to anyone who has existing code using the prior syntax, so they
get a warning + Fix-It to rewrite to the new syntax. Second, we use it
to define builtin macros like `externalMacro` itself, which looks like this:
@expression
public macro externalMacro<T>(module: String, type: String) -> T =
Builtin.ExternalMacro
This uses the same virtual `Builtin` module as other library builtins,
and we can expand it to handle other builtin macro implementations
(such as #line) over time.
Introduce the experimental feature `ParserDiagnostics`, which emits
diagnostics from the new Swift parser *first* for a source file. If
that produces any errors, we suppress any diagnostics emitted from the
C++ parser.
`usesFeatureTypeWrappers` should return `true` for all of
the declarations that use the feature directly or indirectly
e.g. type wrapper types, type wrapped types, and types with
conformance to a type wrapped protocol (with or without wrapper
attribute inference).
Introduce a new behavior when printing references to modules with an
`export_as` definition. Use the `export_as` name in the public swiftinterface
and the real module name in the private swiftinterface.
This has some limits but should still be an improvement over the current
behavior. First, the we use the `export_as` names only for references to clang
decls, not Swift decls with an underlying module defining an `export_as`.
Second, we always print the `export_as` name in the public swiftinterface,
even in the original swiftinterface file when the `export_as` target is likely
not know, so that generated swiftinterface is still broken.
This behavior is enabled by the flags `-enable-experimental-feature ModuleInterfaceExportAs`
or the `SWIFT_DEBUG_USE_EXPORTED_MODULE_NAME_IN_PUBLIC_ONLY` env var. We may
consider turning it on by default in the future.
rdar://98532918
In AliasModuleNames, avoid wrongfully printing aliased names for modules
that were not aliased. This can happen in the case of modules indirectly
imported via a reexport.
rdar://102262019
Although the declaration of macros doesn't appear in Swift source code
that uses macros, they still operate as declarations within the
language. Rework `Macro` as `MacroDecl`, a generic value declaration,
which appropriate models its place in the language.
The vast majority of this change is in extending all of the various
switches on declaration kinds to account for macros.
Ambiguities are introduced in generated swiftinterfaces when a type
shares a name with a module (i.e. XCTest). This workaround uses the
module-alias feature to avoid these ambiguities. Writing module
references with a distinguishable prefix should allow normal
type-checking to avoid the usual ambiguities.
We should still aim for a proper fully-qualified named syntax, but this
may help in the mean time.
rdar://101969500
This is the start of the removal of the C++ implementation of libSyntax
in favor of the new Swift Parser and Swift Syntax libraries. Now that
the Swift Parser has switched the SwiftSyntaxParser library over to
being a thin wrapper around the Swift Parser, there is no longer any
reason we need to retain any libSyntax infrastructure in the swift
compiler.
As a first step, delete the infrastructure that builds
lib_InternalSwiftSyntaxParser and convert any scripts that mention
it to instead mention the static mirror libraries. The --swiftsyntax
build-script flag has been retained and will now just execute the
SwiftSyntax and Swift Parser builds with the just-built tools.
