carton/Sources/CartonHelpers/Async.swift

56 lines
1.4 KiB
Swift

// Copyright 2021 Carton contributors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
import ArgumentParser
extension Sequence {
public func asyncMap<T>(
_ transform: (Element) async throws -> T
) async rethrows -> [T] {
var values = [T]()
for element in self {
try await values.append(transform(element))
}
return values
}
}
/// A type that can be executed as part of a nested tree of commands.
extension AsyncParsableCommand {
public mutating func run() throws {
throw CleanExit.helpRequest(self)
}
}
public protocol AsyncMain {
associatedtype Command: ParsableCommand
}
extension AsyncMain {
public static func main() async {
do {
var command = try Command.parseAsRoot()
if var command = command as? AsyncParsableCommand {
try await command.run()
} else {
try command.run()
}
} catch {
Command.exit(withError: error)
}
}
}