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|
// RUN: %target-swift-frontend %s -emit-sil \
// RUN: -verify \
// RUN: -sil-verify-all \
// RUN: -module-name test \
// RUN: -enable-experimental-feature NonescapableTypes
// REQUIRES: asserts
// REQUIRES: swift_in_compiler
// Simply test that it is possible for a module to define a pseudo-Optional type without triggering any compiler errors.
public protocol ExpressibleByNilLiteral: ~Copyable & ~Escapable {
@_unsafeNonescapableResult
init(nilLiteral: ())
}
@frozen
public enum Nillable<Wrapped: ~Copyable & ~Escapable>: ~Copyable & ~Escapable {
case none
case some(Wrapped)
}
extension Nillable: Copyable where Wrapped: Copyable {}
extension Nillable: Escapable where Wrapped: Escapable {}
extension Nillable: Sendable where Wrapped: ~Copyable & ~Escapable & Sendable { }
extension Nillable: BitwiseCopyable where Wrapped: BitwiseCopyable { }
extension Nillable: ExpressibleByNilLiteral where Wrapped: ~Copyable & ~Escapable {
@_transparent
@_unsafeNonescapableResult
public init(nilLiteral: ()) {
self = .none
}
}
extension Nillable where Wrapped: ~Copyable & ~Escapable {
@_transparent
public init(_ some: consuming Wrapped) { self = .some(some) }
}
extension Nillable where Wrapped: ~Copyable {
public consuming func _consumingMap<U: ~Copyable, E: Error>(
_ transform: (consuming Wrapped) throws(E) -> U
) throws(E) -> U? {
switch consume self {
case .some(let y):
return .some(try transform(y))
case .none:
return .none
}
}
public borrowing func _borrowingMap<U: ~Copyable, E: Error>(
_ transform: (borrowing Wrapped) throws(E) -> U
) throws(E) -> U? {
switch self {
case .some(let y):
return .some(try transform(y))
case .none:
return .none
}
}
}
extension Nillable where Wrapped: ~Copyable {
public consuming func _consumingFlatMap<U: ~Copyable, E: Error>(
_ transform: (consuming Wrapped) throws(E) -> U?
) throws(E) -> U? {
switch consume self {
case .some(let y):
return try transform(consume y)
case .none:
return .none
}
}
public func _borrowingFlatMap<U: ~Copyable, E: Error>(
_ transform: (borrowing Wrapped) throws(E) -> U?
) throws(E) -> U? {
switch self {
case .some(let y):
return try transform(y)
case .none:
return .none
}
}
}
extension Nillable where Wrapped: ~Copyable {
public consuming func _consumingUnsafelyUnwrap() -> Wrapped {
switch consume self {
case .some(let x):
return x
case .none:
fatalError("consumingUsafelyUnwrap of nil optional")
}
}
}
extension Optional where Wrapped: ~Copyable {
internal consuming func _consumingUncheckedUnwrapped() -> Wrapped {
if let x = self {
return x
}
fatalError("_uncheckedUnwrapped of nil optional")
}
}
extension Optional where Wrapped: ~Copyable {
public mutating func _take() -> Self {
let result = consume self
self = nil
return result
}
}
extension Optional where Wrapped: ~Copyable {
public static func ~=(
lhs: _OptionalNilComparisonType,
rhs: borrowing Wrapped?
) -> Bool {
switch rhs {
case .some:
return false
case .none:
return true
}
}
public static func ==(
lhs: borrowing Wrapped?,
rhs: _OptionalNilComparisonType
) -> Bool {
switch lhs {
case .some:
return false
case .none:
return true
}
}
public static func !=(
lhs: borrowing Wrapped?,
rhs: _OptionalNilComparisonType
) -> Bool {
switch lhs {
case .some:
return true
case .none:
return false
}
}
public static func ==(
lhs: _OptionalNilComparisonType,
rhs: borrowing Wrapped?
) -> Bool {
switch rhs {
case .some:
return false
case .none:
return true
}
}
public static func !=(
lhs: _OptionalNilComparisonType,
rhs: borrowing Wrapped?
) -> Bool {
switch rhs {
case .some:
return true
case .none:
return false
}
}
}
public func ?? <T: ~Copyable>(
optional: consuming T?,
defaultValue: @autoclosure () throws -> T
) rethrows -> T {
switch consume optional {
case .some(let value):
return value
case .none:
return try defaultValue()
}
}
public func ?? <T: ~Copyable>(
optional: consuming T?,
defaultValue: @autoclosure () throws -> T?
) rethrows -> T? {
switch consume optional {
case .some(let value):
return value
case .none:
return try defaultValue()
}
}
|
