context errors.swift

public struct Error: ErrorType {
    let source: String; let reason: String
    public init(_ source: String = __FILE__, _ reason: String) {
        self.reason = reason; self.source = source
    }
}

protocol Contextualizable {}
extension Contextualizable {
    func functionContext(function : String = __FUNCTION__) -> String {
        return "\(self.dynamicType):\(function)"
    }
    
    func fileContext(file : String = __FILE__, line : Int = __LINE__) -> String {
        return "\(file):\(line)"
    }
    
    func currentContext(file : String = __FILE__, function : String = __FUNCTION__, line : Int = __LINE__) -> String {
        return "\(self.dynamicType):\(function):\(file):\(line)"
    }
    
    func contextString(items: Any..., file : String = __FILE__, function : String = __FUNCTION__, line : Int = __LINE__) -> String {
        return "\(function):\(self.dynamicType):\(file):\(line) " + items.map({"\($0)"}).joinWithSeparator(", ")
    }
    
    func contextPrint(items: Any..., file : String = __FILE__, function : String = __FUNCTION__, line : Int = __LINE__) {
        print("\(function):\(self.dynamicType):\(file):\(line) " + items.map({"\($0)"}).joinWithSeparator(", "))
    }
    
    func contextError(items: Any..., file : String = __FILE__, function : String = __FUNCTION__, line : Int = __LINE__) -> Error {
        return Error("\(function):\(self.dynamicType):\(file):\(line) ", items.map({"\($0)"}).joinWithSeparator(", "))
    }
}

public struct Parent: Contextualizable {
    func myFunction() throws {
        throw contextError("Some good reason", 2, 3)
    }
}

func dotry(block: () throws -> Void) {
    do {try block()} catch {print(error)}
}


dotry {try Parent().myFunction()}