1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
/*
This source file is part of the Swift.org open source project
Copyright (c) 2014 - 2019 Apple Inc. and the Swift project authors
Licensed under Apache License v2.0 with Runtime Library Exception
See http://swift.org/LICENSE.txt for license information
See http://swift.org/CONTRIBUTORS.txt for Swift project authors
*/
import protocol Foundation.CustomNSError
import var Foundation.NSLocalizedDescriptionKey
extension Result where Failure == Error {
public func tryMap<NewSuccess>(_ closure: (Success) throws -> NewSuccess) -> Result<NewSuccess, Error> {
flatMap({ value in
Result<NewSuccess, Error>(catching: {
try closure(value)
})
})
}
}
/// Represents a string error.
public struct StringError: Equatable, Codable, CustomStringConvertible, Error {
/// The description of the error.
public let description: String
/// Create an instance of StringError.
public init(_ description: String) {
self.description = description
}
}
extension StringError: CustomNSError {
public var errorUserInfo: [String : Any] {
return [NSLocalizedDescriptionKey: self.description]
}
}
extension Result where Failure == StringError {
/// Create an instance of Result<Value, StringError>.
///
/// Errors will be encoded as StringError using their description.
public init(string body: () throws -> Success) {
do {
self = .success(try body())
} catch let error as StringError {
self = .failure(error)
} catch {
self = .failure(StringError(String(describing: error)))
}
}
}
|
