This models the conversion from an uninhabited
value to any type, and allows us to get rid of
a couple of places where we'd attempt to drop
the return statement instead.
First, "can have an absence of Copyable" is a rather confusing notion,
so the query is flipped to "can be Copyable". Next, it's more robust to
ask if a conformance exists for the TypeDecl to answer that question,
rather than trying to replicate what happens within that conformance
lookup.
Also renames `TypeDecl::isEscapable` to match.
Correctly determining the DeclContext needed for an
ExplicitCaughtTypeRequest is tricky for a number of callers, and
mistakes here can easily lead to redundant computation of the caught
type, redundant diagnostics, etc.
Instead, put a `DeclContext` into `DoCatchStmt`, because that's the
only catch node that needs a `DeclContext` but does not have one.
During the review of SE-0413, typed throws, the notion of a `do throws`
syntax for `do..catch` blocks came up. Implement that syntax and
semantics, as a way to explicitly specify the type of error that is
thrown from the `do` body in `do..catch` statement.
The AST verifier was only correctly extracting thrown error types from
enclosing functions, without account for do...catch bodies. Switch it
over to using ASTScope's lookup to find the innermost enclosing caught
error context.
Fixes a AST verifier error reported by Paul Cantrell
Implement type checking support for preamble macros, which expands the
preamble macros and introduces them at the beginning of the function
body prior to type checking. Ensure that the resulting function bodies
type-check properly, including when composing multiple preamble macros
and with a preamble macro applied to the body of a function that
itself came from a body macro.
I've renamed the method to `TypeDecl::isNoncopyable`, because the query
doesn't make sense for many other kinds of `ValueDecl`'s beyond the
`TypeDecl`'s. In fact, it looks like no one was relying on that anyway.
Thus, we now have a distinction where in Sema, you ask whether
a `Type` or `TypeDecl` is "Noncopyable". But within SIL, we still
preserve the notion of "move-only" since there is additionally the
move-only type wrapper for types that otherwise support copying.
Lower the thrown error type into the SIL function type. This requires
very little code because the thrown error type was already modeled as
a SILResultInfo, which carries type information. Note that this
lowering does not yet account for error types that need to passed
indirectly, but we will need to do so for (e.g.) using resilient error
types.
Teach a few places in SIL generation not to assume that thrown types
are always the existential error type, which primarily comes down to
ensuring that rethrow epilogues have the thrown type of the
corresponding function or closure.
Teach throw emission to implicitly box concrete thrown errors in the
error existential when needed to satisfy the throw destination. This
is a temporary solution that helps translate typed throws into untyped
throws, but it should be replaced by a better modeling within the AST
of the points at which thrown errors are converted.
Function bodies are skipped during typechecking when one of the
-experimental-skip-*-function-bodies flags is passed to the frontend. This was
implemented by setting the "body kind" of an `AbstractFunctionDecl` during decl
checking in `TypeCheckDeclPrimary`. This approach had a couple of issues:
- It is incompatible with skipping function bodies during lazy typechecking,
since the skipping is only evaluated during a phase of eager typechecking.
- It prevents skipped function bodies from being parsed on-demand ("skipped" is
a state that is distinct from "parsed", when they ought to be orthogonal).
This needlessly prevented complete module interfaces from being emitted with
-experimental-skip-all-function-bodies.
Storing the skipped status of a function separately from body kind and
requestifying the determination of whether to skip a function solves these
problems.
Resolves rdar://116020403
These allow multi-statement `if`/`switch` expression
branches that can produce a value at the end by
saying `then <expr>`. This is gated behind
`-enable-experimental-feature ThenStatements`
pending evolution discussion.
* Weakly reference ModuleDecl from PackageUnit
* Add PackageUnit decl context getter and use it for a package AccessScope
* Return module decl referenced by PackageUnit in getModuleScopeContext and getParentModule
* Handle package acl in access scope checkers
* Remove AccessLimitKind
* Fix tests
Resolves rdar://104987295, rdar://105187216, rdar://104723918
Always use `Decl::visitAuxiliaryDecls` to visit decls produced by macros, including peer macros and declaration macros. Use name-driven expansion for peer macros. Remove `MacroExpansionDecl::getRewritten()`.
Also make `ExpandMacroExpansionDeclRequest` cache the buffer ID (similar to other macros) instead of an array of decls.
Provide ASTWalker with a customization point to specify whether to
check macro arguments (which are type checked but never emitted), the
macro expansion (which is the result of applying the macro and is
actually emitted into the source), or both. Provide answers for the
~115 different ASTWalker visitors throughout the code base.
Fixes rdar://104042945, which concerns checking of effects in
macro arguments---which we shouldn't do.
- Remove the `Rewritten` field and `setRewritten()`. Make `getRewritten()` invoke the request.
- Rename fields `Macro` and `MacroLoc` to `MacroName` and `MacroNameLoc` respectively as well as their getters to match those in `MacroExpansionExpr`.
