Fixed up name based extractors

Author: mdedetrich

js/src/main/scala/scalajson/ast/JValue.scala

@@ -137,6 +137,7 @@ final case class JNumber private[ast] (value: String) extends JValue {
   */
 // Implements named extractors so we can avoid boxing
 sealed abstract class JBoolean extends JValue {
+  def isEmpty: Boolean = false
   def get: Boolean
 
   override def toJsAny: js.Any = get

js/src/main/scala/scalajson/ast/unsafe/JValue.scala

@@ -107,6 +107,7 @@ final case class JNumber(value: String) extends JValue {
   */
 // Implements named extractors so we can avoid boxing
 sealed abstract class JBoolean extends JValue {
+  def isEmpty: Boolean = false
   def get: Boolean
 
   override def toJsAny: js.Any = get

jvm/src/main/scala/scalajson/ast/JValue.scala

@@ -115,6 +115,7 @@ final case class JNumber private[ast] (value: String) extends JValue {
   */
 // Implements named extractors so we can avoid boxing
 sealed abstract class JBoolean extends JValue {
+  def isEmpty: Boolean = false
   def get: Boolean
 }
 

jvm/src/main/scala/scalajson/ast/unsafe/JValue.scala

@@ -85,6 +85,7 @@ final case class JNumber(value: String) extends JValue {
   */
 // Implements named extractors so we can avoid boxing
 sealed abstract class JBoolean extends JValue {
+  def isEmpty: Boolean = false
   def get: Boolean
 }