mirror of
https://github.com/apple/swift-foundation.git
synced 2025-05-23 22:13:35 +08:00
4823a260fd
To enable building this package with a "minimal" Swift toolchain whose compiler does not have support for macros, guard the macro declarations behind `#if hasFeature(Macros)`. This has no effect on anything but the toolchain bootstrap process.
35 lines
1.5 KiB
Swift
35 lines
1.5 KiB
Swift
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This source file is part of the Swift.org open source project
|
|
//
|
|
// Copyright (c) 2024 Apple Inc. and the Swift project authors
|
|
// Licensed under Apache License v2.0 with Runtime Library Exception
|
|
//
|
|
// See https://swift.org/LICENSE.txt for license information
|
|
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
@available(FoundationPredicate 0.4, *)
|
|
public struct Expression<each Input, Output> : Sendable {
|
|
public let expression : any StandardPredicateExpression<Output>
|
|
public let variable: (repeat PredicateExpressions.Variable<each Input>)
|
|
|
|
public init(_ builder: (repeat PredicateExpressions.Variable<each Input>) -> any StandardPredicateExpression<Output>) {
|
|
self.variable = (repeat PredicateExpressions.Variable<each Input>())
|
|
self.expression = builder(repeat each variable)
|
|
}
|
|
|
|
public func evaluate(_ input: repeat each Input) throws -> Output {
|
|
try expression.evaluate(
|
|
.init(repeat (each variable, each input))
|
|
)
|
|
}
|
|
}
|
|
|
|
#if hasFeature(Macros)
|
|
@freestanding(expression)
|
|
@available(FoundationPredicate 0.4, *)
|
|
public macro Expression<each Input, Output>(_ body: (repeat each Input) -> Output) -> Expression<repeat each Input, Output> = #externalMacro(module: "FoundationMacros", type: "ExpressionMacro")
|
|
#endif
|