lazy-exprs.scala:38: warning: match may not be exhaustive. It would fail on the following input: Some((x: String forSome x not in Z1)) t match { ^ lazy-exprs.scala:62: warning: match may not be exhaustive. It would fail on the following input: Some((x: String forSome x not in LazyField)) t match { ^ forced lazy val in scrutinee: ok forced lazy val in case: ok lazy val in case: forced ok lazy val in if condition: forced ok lazy val in pattern: forced LazyField ok lazy val with patterns: x and y: xy(x, y) x1 and y1: x1y1(x1, y1)