CODEWITHSUNDEEP
scalaprotocol-buffers
Anthony
Anthony

Reputation: 35988

Type mismatch expected: Option[Color], actual: Color

I have a case class like this:

case class ColorDetail(
    color: Option[Color],
    shades: List[Shade]
)

I have a method with this signature:

def colorFromProtoBuf(msg: ColorMessage): Color = {
 ...
}

When I try to do:

ColorDetail(
   color = colorFromtProtoBuf(...), //Type mismatch here
   shades = ...
)

I get a 

Type mismatch, expected: Option[Color], actual: Color

How can I resolve this without changing my case class or method signature. Ideally I would like to just change the line where I'm getting an error. Is there a way I can convert it to Option[Color] instead of just Color

Upvotes: 0

Views: 292

Answers (2)

Tim
Tim

Reputation: 27421

If colorFromProtoBuf is guaranteed to succeed you can simply wrap it in Some:

color = Some(colorFromProtoBuf(...))

If colorFromProtoBuf might return null then use Option which will convert null values to None:

color = Option(colorFromProtoBuf(...))

If there is a chance that colorFromProtoBuf might throw an error then use Try:

color = Try(colorFromProtoBuf(...)).toOption

Finally, if colorFromProtoBuf might fail and you can edit this function, change the signature to return Option[Color] and return None on failure or Some(color) on success.

def colorFromProtoBuf(msg: ColorMessage): Option[Color] = {

(I know this is not a one-line answer, but it might be the correct answer!)

Upvotes: 3

Terry Dactyl
Terry Dactyl

Reputation: 1868

color = Option(colorFromtProtoBuf(...))

color will be assigned to Some(Color) or None if your function returns null

Upvotes: 4

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