OptionSugar

Trait providing an implicit class that adds a toOr method to Option, which converts Some to Good, None to Bad.

You can use the toOr method to record information about why a processing of nested Options resulted in None. For example, the following for expression results in None if either the passed optional Person is None or else if the contained optional age is None:

scala> case class Person(name: String, age: Option[Int])
defined class Person

scala> def ageOf(person: Option[Person]) =
     |   for {
     |     per <- person
     |     age <- per.age
     |   } yield age
ageOf: (person: Option[Person])Option[Int]

scala> ageOf(Some(Person("Ralph", Some(32))))
res0: Option[Int] = Some(32)

scala> ageOf(Some(Person("Curt", None)))
res3: Option[Int] = None

scala> ageOf(None)
res2: Option[Int] = None

If you instead populate the for expression with Ors, supplying an error message or other "bad" value to the toOr method in case of None, you'll get an indication of which part failed if a None is encountered:

scala> import OptionSugar._
import OptionSugar._

scala> def ageOf(person: Option[Person]) =
    |   for {
    |     per <- person toOr "no person here"
    |     age <- per.age toOr "ageless person"
    |   } yield age
ageOf: (person: Option[Person])org.scalactic.Or[Int,String]

scala> ageOf(Some(Person("Ralph", Some(32))))
res1: org.scalactic.Or[Int,String] = Good(32)

scala> ageOf(Some(Person("Curt", None)))
res2: org.scalactic.Or[Int,String] = Bad(ageless person)

scala> ageOf(None)
res3: org.scalactic.Or[Int,String] = Bad(no person here)