Error.swift

public extension JSON {
    public enum Error: Swift.Error {
        case missing(path: Path)
        case typeMismatch(expected: Any.Type, actualValue: Any, path: Path)
        case unexpected(value: Any?, path: Path)
        case dataCorrupted(value: Any, description: String)
        case other(description: String)
    }
}

// MARK: - CustomStringConvertible

extension JSON.Error: CustomStringConvertible {
    public var description: String {
        switch self {
        case let .missing(path: path):
            return "missing(path: \(path))"
            
        case let .typeMismatch(expected: expected, actualValue: actualValue, path: path):
            return "typeMismatch(expected: \(expected), actualValue: \(actualValue), path: \(path))"
            
        case let .unexpected(value: value, path: path):
            return "unexpected(value: \(String(describing: value)), path: \(path))"
            
        case let .dataCorrupted(value: value, description: description):
            return "dataCorrupted(value: \(value), description: \(description))"
            
        case let .other(description: description):
            return "other(description: \(description))"
        }
    }
}

// MARK: - CustomDebugStringConvertible

extension JSON.Error: CustomDebugStringConvertible {
    public var debugDescription: String {
        return description
    }
}