scala - Pattern matching on case classes with * (varargs) parameter -

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i have 2 case class like:

case class b(value:int) case class a(a:string, b:b*) extends alike

and want pattern match on instance of a:

def foo(al:alike) = {   al match {     case a(a, bs) => ...   } }

scalac doesn't understand bs seq[b] , thinks 1 b. why case , how should pattern match on it?

it's varargs argument, need explain compiler explicitly. use following case expression:

def foo(al:alike) = {   al match {     case a(a, bs @ _*) => ...   } }

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