Wrap the `InheritedEntry` array available on both `ExtensionDecl` and
`TypeDecl` in a new `InheritedTypes` class. This class will provide shared
conveniences for working with inherited type clauses. NFC.
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.
`ASTWalker` was missing a walk into the generic arguments for
freestanding declarations and expressions. `SemaAnnotator` was missing
the walk into the `TypeRepr` when walking over custom attributes.
Resolves rdar://110856428.
When you have a type that's ambiguous because it's defined in 2 imported
modules, but you don't have to disambiguate by using the module name,
previously no index references were produced. Now most are for the
common case, but notably nested type constructors and generics still
aren't emitted, partially because of https://github.com/apple/swift/issues/65726
Fixes: https://github.com/apple/swift/issues/64598
Some places want to do in-order walks of MacroExpansionDecls, but still
visit auxiliary declarations. Rather than force them to specifically
filter out declarations from the MacroExpansionDecl, add a parameter to
visitAuxiliaryDecls to skip them.
Before this change it was possible to:
1. Call mutating methods on a consume result.
2. assign into a consume (e.x.: var x = ...; (consume x) = value.
From an implementation perspective, this involved just taking the logic I
already used for the CopyExpr and reusing it for ConsumeExpr with some small
tweaks.
rdar://109479440
Some notes:
1. I implemented this as a contextual keyword that can only apply directly to
lvalues. This ensures that we can still call functions called copy, define
variables named copy, etc. I added tests for both the c++ and swift-syntax based
parsers to validate this. So there shouldn't be any source breaks.
2. I did a little bit of type checker work to ensure that we do not treat
copy_expr's result as an lvalue. Otherwise, one could call mutating functions on
it or assign to it, which we do not want since the result of copy_value is
3. As expected, by creating a specific expr, I was able to have much greater
control of the SILGen codegen and thus eliminate extraneous copies and other
weirdness than if we used a function and had to go through SILGenApply.
rdar://101862423
SE-390 concluded with choosing the keyword discard rather than forget for
the statement that disables the deinit of a noncopyable type. This commit
adds parsing support for `discard self` and adds a deprecation warning for
`_forget self`.
rdar://108859077
Previously we were skipping the macro’s definition (i.e. the part after `=` in a macro declaration if it wasn’t type checked. Since syntactic rename doesn’t type-check anything, it was thus skippin the macro definition. Add a flag to `ASTWalker` that allows `NameMatcher` to opt-out of this behavior.
inside closures while type checking a macro expansion.
PreCheckExpr, ConstraintGenerator, and other walkers do not walk into macro
expansions. However, the implementation of this macro walking behavior in
ASTWalker would skip any declaration that appears inside any macro expansion
buffer. This is incorrect for cases where the parent is in the same macro
expansion buffer, because the local declaration is not inside a new macro
expansion. This caused bogus errors when type checking expanded macro expressions
containing closures with local declarations, because pre-check and constraint
generation mistakenly skipped local pattern bindings.
These expressions are a little tricky, because we don't always
type-check them in the way that clients would expect. We might want to
change the representation here, but until then... don't walk the
untypechecked ones.
This replaces `synthesizeTildeEqualsOperatorApplication`,
and synthesizes the match expression and var
on-demand.
Additionally, it pushes the lookup logic into
pre-checking.
Allow freestanding macros to be used at top-level.
- Parse top-level `#…` as `MacroExpansionDecl` when we are not in scripting mode.
- Add macro expansion decls to the source lookup cache with name-driven lazy expansion. Not supporting arbitrary name yet.
- Experimental support for script mode and brace-level declaration macro expansions: When type-checking a `MacroExpansionExpr`, assign it a substitute `MacroExpansionDecl` if the macro reference resolves to a declaration macro. This doesn’t work quite fully yet and will be enabled in a future fix.
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.
Currently, this is staged in as `_forget`,
as part of SE-390. It can only be used on
`self` for a move-only type within a consuming
method or accessor. There are other rules, see
Sema for the details.
A `forget self` really just consumes self and
performs memberwise destruction of its data.
Thus, the current expansion of this statement
just reuses what we inject into the end of a
deinit.
Parsing of `forget` is "contextual".
By contextual I mean that we do lookahead to
the next token and see if it's identifier-like.
If so, then we parse it as the `forget` statement.
Otherwise, we parse it as though "forget" is an
identifier as part of some expression.
This way, we won't introduce a source break for
people who wrote code that calls a forget
function.
This should make it seamless to change it from
`_forget` to `forget` in the future.
resolves rdar://105795731
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.
This lets us consolidate code paths that mostly run in parallel over the
existing InOutTypeRepr/SharedTypeRepr/OwnedTypeRepr family of types. This
patch by itself is NFC but makes it easier to introduce new spellings,
particularly the newly-official `borrowing` and `consuming` modifiers
that were approved in SE-0377.
Various requests expect to be walking over the current source file.
While we could add checks to all these to skip decls outside of the
current buffer, it's a little nicer to handle this during the walk
instead.
Allow ignoring nodes that are from macro expansions and add that flag to
the various walks that expect it.
Also add a new `getOriginalAttrs` that filters out attributes in
generated source.
Introduce SingleValueStmtExpr, which allows the
embedding of a statement in an expression context.
This then allows us to parse and type-check `if`
and `switch` statements as expressions, gated
behind the `IfSwitchExpression` experimental
feature for now. In the future,
SingleValueStmtExpr could also be used for e.g
`do` expressions.
For now, only single expression branches are
supported for producing a value from an
`if`/`switch` expression, and each branch is
type-checked independently. A multi-statement
branch may only appear if it ends with a `throw`,
and it may not `break`, `continue`, or `return`.
The placement of `if`/`switch` expressions is also
currently limited by a syntactic use diagnostic.
Currently they're only allowed in bindings,
assignments, throws, and returns. But this could
be lifted in the future if desired.
This is needed for general fidelity in SIL, since generic argument
lists are used for a lot of different things that aren't restricted
from containing multiple packs. I haven't actually done the work to
use Pack structure to disambiguate the resolution of pack parameters,
but this is a good start.
We'll probably need something like this in source eventually, so
there's no reason to regret adding all the infrastructure for it.
Add support for freestanding declaration macros.
- Parse `@declaration` attribute.
- Type check and expand `MacroExpansionDecl`.
Known issues:
- Generic macros are not yet handled.
- Expansion does not work when the parent decl context is `BraceStmt`. Need to parse freestanding declaration macro expansions in `BraceStmt` as `MacroExpansionDecl`, and add expanded decls to name lookup.
pack expansion type reprs.
Classic variadic parameters still use the postfix ellipsis syntax, and
pack expansion types now use a prefix 'repeat' keyword.
