Like switch cases, a catch clause may now include a comma-
separated list of patterns. The body will be executed if any
one of those patterns is matched.
This patch replaces `CatchStmt` with `CaseStmt` as the children
of `DoCatchStmt` in the AST. This necessitates a number of changes
throughout the compiler, including:
- Parser & libsyntax support for the new syntax and AST structure
- Typechecking of multi-pattern catches, including those which
contain bindings.
- SILGen support
- Code completion updates
- Profiler updates
- Name lookup changes
`@differentiable` attributes may contain `where` clauses referencing generic
parameters from some generic context, just like `@_specialize` attributes.
Without special ASTScope support for `@differentiable` attributes,
ASTScopeLookup.cpp logic tries to resolve the generic parameter `DeclName`s in
`where` clauses based on source location alone
(`ASTScopeImpl::findChildContaining`) and fails.
The fix is to add a special `DifferentiableAttributeScope`, mimicking
`SpecializeAttributeScope`. Every `@differentiable` attribute has its own scope,
derived from the declaration on which it is declared. Unlike `@_specialize`,
`@differentiable` may also be declared on `AbstractStorageDecl` declarations
(subscripts and variables).
Upstreams https://github.com/apple/swift/pull/27451.
Progress towards TF-828: upstream `@differentiable` attribute type-checking.
This commit introduces a request to type-check a
default argument expression and splits
`getDefaultValue` into 2 accessors:
- `getStructuralDefaultExpr` which retrieves the
potentially un-type-checked default argument
expression.
- `getTypeCheckedDefaultExpr` which retrieves a
fully type-checked default argument expression.
In addition, this commit adds `hasDefaultExpr`,
which allows checking for a default expr without
kicking off a request.
Like the last commit, SourceFile is used a lot by Parse and Sema, but
less so by the ClangImporter and (de)Serialization. Split it out to
cut down on recompilation times when something changes.
This commit does /not/ split the implementation of SourceFile out of
Module.cpp, which is where most of it lives. That might also be a
reasonable change, but the reason I was reluctant to is because a
number of SourceFile members correspond to the entry points in
ModuleDecl. Someone else can pick this up later if they decide it's a
good idea.
No functionality change.
Most of AST, Parse, and Sema deal with FileUnits regularly, but SIL
and IRGen certainly don't. Split FileUnit out into its own header to
cut down on recompilation times when something changes.
No functionality change.
A number of callers to AbstractFunctionDecl::getBody() were only
extracting the source range of the body... which can be retrieved more
efficiently with getBodySourceRange().
