writing json is working

src/main/scala/co.blocke.scalajack/Codec.scala → src/main/scala/co.blocke.scalajack/ScalaJack.scala

@@ -6,7 +6,7 @@ import scala.quoted.*
 import quoted.Quotes
 import json.*
 
-object Codec:
+object ScalaJack:
 
   inline def write[T](t: T)(using cfg: JsonConfig = JsonConfig()): String = ${ writeImpl[T]('t, 'cfg) }
 

src/main/scala/co.blocke.scalajack/json/JsonConfig.scala

@@ -4,8 +4,13 @@ package json
 case class JsonConfig(
     noneAsNull: Boolean = false,
     tryFailureHandling: TryOption = TryOption.NO_WRITE,
-    typeHint: String = "_hint",
-    enumsAsIds: Char | List[String] = Nil // Char is '*' for all enums as ids
+    // --------------------------
+    typeHintLabel: String = "_hint",
+    typeHintLabelByTrait: Map[String, String] = Map.empty[String, String], // Trait name -> type hint label
+    typeHintDefaultTransformer: String => String = (v: String) => v, // in case you want something different than class name (simple name re-mapping)
+    typeHintTransformer: Map[String, Any => String] = Map.empty[String, Any => String], // if you want class-specific control (instance value => String)
+    // --------------------------
+    enumsAsIds: Char | List[String] = Nil // Char is '*' for all enums as ids, or a list of fully-qualified class names
 )
 
 enum TryOption:

src/main/scala/co.blocke.scalajack/json/JsonWriter.scala

@@ -28,11 +28,6 @@ object JsonWriter:
   def writeJsonFn[T](rtRef: RTypeRef[T])(using tt: Type[T], q: Quotes): Expr[(T, StringBuilder, JsonConfig) => StringBuilder] =
     import quotes.reflect.*
 
-    // def liftFunction[T: Type, U: Type](f: T => U): Expr[T => U] = {
-    //   val fnExpr: Expr[T => U] = '{ (x: T) => ${ f('x) } }
-    //   fnExpr
-    // }
-
     rtRef match
       case rt: PrimitiveRef[?] if rt.isStringish =>
         '{ (a: T, sb: StringBuilder, cfg: JsonConfig) =>
@@ -75,14 +70,18 @@ object JsonWriter:
             val sbLen = sb.length
             ${
               val hintStmt = (rt match
-                case s: ScalaClassRef[?] if s.renderHint =>
+                case s: ScalaClassRef[?] if s.renderTrait.isDefined =>
+                  val traitName = Expr(s.renderTrait.get)
                   '{
                     sb.append('"')
-                    sb.append(cfg.typeHint)
+                    sb.append(cfg.typeHintLabelByTrait.getOrElse($traitName, cfg.typeHintLabel))
                     sb.append('"')
                     sb.append(':')
                     sb.append('"')
-                    sb.append(a.getClass.getName)
+                    val hint = cfg.typeHintTransformer.get(a.getClass.getName) match
+                      case Some(xform) => xform(a)
+                      case None        => cfg.typeHintDefaultTransformer(a.getClass.getName)
+                    sb.append(hint)
                     sb.append('"')
                     sb.append(',')
                     ()

src/main/scala/co.blocke.scalajack/json/ReflectUtil.scala

@@ -10,8 +10,7 @@ import scala.quoted.staging.*
 
 object ReflectUtil:
 
-  /**
-    * This function takes the RType of a trait and an instance of T and does two things.
+  /** This function takes the RType of a trait and an instance of T and does two things.
     * First it expresses the instance's class *in terms of* the trait's concrete type parameters (if any).
     * Then it generates a writer function for the now correctly-typed class.
     *
@@ -46,7 +45,7 @@ object ReflectUtil:
 
       inTermsOfRef.refType match
         case '[t] =>
-          val asClassRef = inTermsOfRef.asInstanceOf[ScalaClassRef[t]].copy(renderHint = true)
+          val asClassRef = inTermsOfRef.asInstanceOf[ScalaClassRef[t]].copy(renderTrait = Some(traitType.name))
           JsonWriter.writeJsonFn[t](asClassRef.asInstanceOf[RTypeRef[t]])
     }
     val writeFn = run(fn)

src/main/scala/co.blocke.scalajack/run/Play.scala

@@ -10,12 +10,25 @@ object RunMe extends App:
   val d = Dog("Fido", 4, 2, Some(Dog("Mindy", 4, 0, None)))
   val d2 = Dog("Spot", 4, 3, Some(Dog("Floppy", 3, 1, None)))
 
-  val cfg = json.JsonConfig()
-  println(Codec.write(d)(using cfg))
+  val mapper = (a: Any) =>
+    a.getClass.getPackage.getName match
+      case p if p.startsWith("co.blocke") => "Blocke"
+      case x                              => "Something " + x.getClass.getName
+
+  given json.JsonConfig = json
+    .JsonConfig()
+    .copy(
+      typeHintDefaultTransformer = (s: String) => s.split("\\.").last,
+      typeHintLabelByTrait = Map("co.blocke.scalajack.run.Animal" -> "kind"),
+      typeHintTransformer = Map("co.blocke.scalajack.run.Dog" -> mapper)
+    )
+
+  println(ScalaJack.write(d))
+
   val t0 = System.currentTimeMillis()
   for i <- 0 to 10000 do
-    Codec.write(d)(using cfg)
-    if i % 100 == 0 then println(i)
+    ScalaJack.write(d)
+    // if i % 100 == 0 then println(i)
     // if i == 10000 then println(i)
 
   // println(Codec.write(d)(using cfg))

src/main/scala/co.blocke.scalajack/run/Sample.scala

@@ -9,7 +9,12 @@ trait Animal:
   val numLegs: Int
   val friend: Option[Animal]
 
-case class Dog(name: String, numLegs: Int, carsChased: Int, friend: Option[Animal]) extends Animal
+trait Animal2:
+  val name: String
+  val numLegs: Int
+  val friend: Option[Animal2]
+
+case class Dog(name: String, numLegs: Int, carsChased: Int, friend: Option[Animal2]) extends Animal2
 
 enum Colors:
   case Red, Blue, Green