More idiomatic Result API - #42
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Extension methods are still potentially causing colisions, so lets avoid in most cases. - Move all methods from companion extension blocks into the enum body, using stdlib-style lower bounds (getOrElse[T1 >: T], flatMap[U, E1 >: E], etc.) and evidence-based flatten/toTry like Either's. The sources move from package.scala to Result.scala. - Rename `or` to `orElse` and `getNullable` to `orNull` (with Option.orNull's signature); tap/tapErr now take f: T => U per the existing TODOs. - Keep extensions only where required: Result.eval (unchanged), the right-associative *: operator, and ScalaConverters on stdlib types (which would become real methods if merged into the stdlib). - Remove the unidiomatic ResultIsErrException case class; get now throws a plain NoSuchElementException like Option.get. - Add Result.catching to construct a Result from a NonFatal-throwing body, with tests covering success, caught, and fatal rethrow cases.
natsukagami
approved these changes
Jul 29, 2026
| * [[Err]]. | ||
| * @group access | ||
| */ | ||
| def orNull[T1 >: T](using ev: Null <:< T1): T1 = this match |
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How would inference deal with this? 🤔 it looks complicated, most of the time I just want T | Null, but is it not possible because of variance?
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I lifted the signature from Option, which infers like this:
scala> Some(1).orNull
val res0: Int | Null = 1
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a type variable does give the option to infer a nicer type as well - e.g. for getOrElse it could infer the sealed trait type rather than a straight union of value | default
scala> def getOrElse2[A, B](a: Option[A])(b: => B): A | B = a match
case Some(a1) => a1
case _ => b
def getOrElse2[A, B](a: Option[A])(b: => B): A | B
scala> sealed trait Bar; case class X() extends Bar; case class Y() extends Bar
// defined trait Bar
// defined case class X
// defined case class Y
scala> Some(X()).getOrElse(Y())
val res4: Bar = X() // type variable picks a nicer target
scala> getOrElse2(Some(X()))(Y())
val res5: X | Y = X() // union is too precise
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Just seen that Option adopted a new signature, so lets follow that:
final def orNull[A1 >: A | Null]: A1 = ???
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Sounds good :) I think we should also compile with strict nulls
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In preparation to make Result stable for standard library: