This is one of the features of Scala I like; explicit types for Option/Some/None in the core language and standard API. It's generally used for return types (ex

This is one of the features of Scala I like; explicit types for Option/Some/None in the core language and standard API. It's generally used for return types (ex: a hashmap 'get' will have a return type of Option[ValueType] and return either Some[ValueType] or None) but you can use it for function parameters as well. scala> def foo(name:Option[String] = None, age:Option[Int] = None) = { | println("==========") | if( name.isDefined ) | println("Name: " + name.get) | if( age.isDefined ) | println("Age: " + age.get) | println("==========") | } foo: (name: Option[String], age: Option[Int])Unit scala> foo() ========== ========== scala> foo(Some("Alice")) ========== Name: Alice ========== scala> foo(age = Some(10)) ========== Age: 10 ========== Plus with some implicit syntactic sugar... scala> implicit def strToSome(s:String) = Some(s) strToSome: (s: String)Some[String] scala> implicit def intToSome(i:Int) = Some(i) intToSome: (i: Int)Some[Int] scala> foo("Alice") ========== Name: Alice ========== scala> foo(name = "Alice") ========== Name: Alice ========== scala> foo(age = 10) ========== Age: 10 ========== scala> foo(name = "Alice", age = 10) ========== Name: Alice Age: 10 ==========