Follow the feature flag convention for capitalization and be
consistent with the related NoncopyableGenerics feature.
This is a new feature that no wild Swift code has used it yet:
commit e99ce1cc5d
Author: Kavon Farvardin <kfarvardin@apple.com>
Date: Tue Dec 5 23:25:09 2023
[NCGenerics] add `~Escapable`
Basic implementation of `~Escapable` in the type system.
The number of errors in a function scope can scale exponentially,
making it hard to root cause and resolve unless we group them into
a single error. Grouping the error diagnostics will considerably
improve the concurrency user experience.
Function body macros allow one to introduce a function body for a
particular function, either providing a body for a function that
doesn't have one, or wholesale replacing the body of a function that
was written with a new one.
There's no reason to generate only TypeRepr using ASTGen anymore.
Use ParserASTGen feature to test test/ASTGen/types.swift because
ASTGen now can generate the whole test file for type checking.
Introduce the upcoming feature `FullTypedThrows`. When enabled, infer
the error type of a `throw` statement based on its original type,
instead of always being `any Error`. This is technically a
source-breaking change, hence the upcoming feature flag.
Always print the real module name for references in private
swiftinterfaces, ignoring export-as declarations. Keep using the
export-as name for the public swiftinterface only.
The flag `ModuleInterfaceExportAs` used to enable this behavior and
we're removing it to make it the default.
rdar://115922907
The feature InternalImportsByDefault makes imports default to internal instead
of public. Applying the Swift 6 behavior of SE-0409 in Swift 5.
Let's use only that flag to track the Swift 6 behavior as well instead
of separately checking for the language version.
Type checking a default argument expression will compute the required
actor isolation for evaluating that argument value synchronously. Actor
isolation checking is deferred to the caller; it is an error to use a
default argument from across isolation domains.
Currently gated behind -enable-experimental-feature IsolatedDefaultArguments.
This looks like it was never properly implemented, since when we generate the
memberwise initializer for the struct in SILGen, it incorrectly tries to apply
the entire initializer expression to each variable binding in the pattern,
rather than destructuring the result and pattern-matching it to the variables.
Since it never worked it doesn't look like anyone is using this, so let's
put up an error saying it's unsupported until we can implement it properly.
Add `StructLetDestructuring` as an experimental feature flag so that tests around
the feature for things like module interface printing can still work.
Add the thrown type into the AST representation of function types,
mapping from function type representations and declarations into the
appropriate thrown type. Add tests for serialization, printing, and
basic equivalence of function types that have thrown errors.
An initial implementation of a rework in how
we prevent noncopyable types from being
substituted in places they are not permitted.
Instead of generating a constraint for every
generic parameter in the solver, we produce
real Copyable conformance requirements. This
is much better for our longer-term goal of
supporting `~Copyable` in more places.
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.