definition as typeclass

src/main/scala/com/htmlism/mos6502/dsl/Address.scala

@@ -11,7 +11,7 @@ object ZeroAddress {
         MemoryLocation
 
       def toShow(x: ZeroAddress): String =
-        String.format("global address 0x%02x", x.n)
+        String.format("zero address 0x%02x", x.n)
 
       def toDefinitionLiteral(x: ZeroAddress): String =
         toAddressLiteral(x)

src/main/scala/com/htmlism/mos6502/dsl/AsmDocumentContext.scala

@@ -64,8 +64,8 @@ class DefinitionGroupContext {
   private val xs: ListBuffer[Definition[_]] =
     ListBuffer()
 
-  def push(x: Definition[_]): Unit =
-    xs.append(x)
+  def push[A](x: A)(implicit ev: Definable[A]): Unit =
+    xs.append(ev.toDefinition(x))
 
   def toGroup(s: String): DefinitionGroup =
     DefinitionGroup(s, xs.toList)
@@ -77,6 +77,14 @@ case class Definition[A: Operand](name: String, x: A) {
       .toDefinitionLiteral(x)
 }
 
+object Definition {
+  implicit def definitionDefinable[A]: Definable[Definition[A]] =
+    new Definable[Definition[A]] {
+      def toDefinition(x: Definition[A]) =
+        x
+    }
+}
+
 class AsmBlockContext {
   private val xs: ListBuffer[Statement] =
     ListBuffer()

src/main/scala/com/htmlism/mos6502/dsl/Definable.scala

@@ -0,0 +1,5 @@
+package com.htmlism.mos6502.dsl
+
+trait Definable[A] {
+  def toDefinition(x: A): Definition[_]
+}

src/main/scala/com/htmlism/mos6502/dsl/ReadWriteLocation.scala

@@ -18,3 +18,11 @@ case class ReadWriteLocation[A](name: String, address: Address) {
     //    ctx.push(STA, ev, s"write ${ev.toShow(x)} to $name ($n)")
   }
 }
+
+object ReadWriteLocation {
+  implicit def readWriteLocationDefinable[A]: Definable[ReadWriteLocation[A]] =
+    new Definable[ReadWriteLocation[A]] {
+      def toDefinition(x: ReadWriteLocation[A]): Definition[ZeroAddress] =
+        Definition(x.name, 0x00.z)
+    }
+}

src/main/scala/com/htmlism/mos6502/dsl/VolatileDevice.scala

@@ -15,3 +15,11 @@ case class VolatileDevice[A](name: String, address: Address) {
 //    ctx.push(LDA, ev, s"write ${ev.toShow(x)} to $name ($n)")
   }
 }
+
+object VolatileDevice {
+  implicit def volatileDeviceDefinable[A]: Definable[VolatileDevice[A]] =
+    new Definable[VolatileDevice[A]] {
+      def toDefinition(x: VolatileDevice[A]): Definition[ZeroAddress] =
+        Definition(x.name, 0x00.z)
+    }
+}

src/main/scala/com/htmlism/mos6502/dsl/syntax/AsmDocSyntax.scala

@@ -15,17 +15,14 @@ trait AsmDocSyntax {
       .push(asmCtx.toFragment)
   }
 
-  def group[A](s: String)(f: DefinitionGroupContext => A)(implicit ctx: AsmDocumentContext): A = {
+  def group[A](s: String)(f: DefinitionGroupContext => A)(implicit ctx: AsmDocumentContext): Unit = {
     val g: DefinitionGroupContext =
       new DefinitionGroupContext
 
-    val ret =
-      f(g)
+    f(g)
 
     ctx
       .push(g.toGroup(s))
-
-    ret
   }
 
   def enum[A](implicit ctx: AsmDocumentContext, ev: EnumAsm[A]): Unit = {

src/test/scala/com/htmlism/mos6502/dsl/DslSpec.scala

@@ -9,51 +9,13 @@ class DslSpec extends AnyFlatSpec with should.Matchers {
   "the dsl" should "compile" in {
     val doc =
       asmDoc { implicit ctx =>
-        group("snake things") { implicit g =>
-          (define("snakeBodyStart", 0x12.z), define("snakeDirection", 0x02.z), define("snakeLength", 0x03.z))
-        }
-
-        group("ASCII values of keys controlling the snake") { implicit g =>
-          (define("ASCII_w", 0x77.z), define("ASCII_a", 0x61.z), define("ASCII_s", 0x73.z), define("ASCII_d", 0x64.z))
-        }
-
-        group("System variables") { implicit g =>
-          (define("sysRandom", 0xfe.z), define("sysLastKey", 0xff.z))
-        }
-
         group("constants test") { implicit g =>
           (constant("margin", 16), constant("secret", 42))
         }
-
-        ()
       }
 
     doc shouldEqual AsmDocument(
       List(
-        DefinitionGroup(
-          "snake things",
-          List(
-            Definition("snakeBodyStart", 0x12.z),
-            Definition("snakeDirection", 0x02.z),
-            Definition("snakeLength", 0x03.z)
-          )
-        ),
-        DefinitionGroup(
-          "ASCII values of keys controlling the snake",
-          List(
-            Definition("ASCII_w", 0x77.z),
-            Definition("ASCII_a", 0x61.z),
-            Definition("ASCII_s", 0x73.z),
-            Definition("ASCII_d", 0x64.z)
-          )
-        ),
-        DefinitionGroup(
-          "System variables",
-          List(
-            Definition("sysRandom", 0xfe.z),
-            Definition("sysLastKey", 0xff.z)
-          )
-        ),
         DefinitionGroup(
           "constants test",
           List(

src/test/scala/com/htmlism/mos6502/dsl/snake/Easy6502Spec.scala

@@ -68,8 +68,8 @@ class Easy6502Spec extends AnyFlatSpec with should.Matchers {
   }
 
   "snake" should "compile" in {
-    val sysRandom      = VolatileDevice[Int]("sysRandom", 0xfe.z)
-    val sysLastKey     = VolatileDevice[AsciiValue]("sysLastKey", 0xff.z)
+    val sysRandom  = VolatileDevice[Int]("sysRandom", 0xfe.z)
+    val sysLastKey = VolatileDevice[AsciiValue]("sysLastKey", 0xff.z)
 
     val appleLocation  = ReadWriteLocation[Int]("appleLocation", 0x00.z)
     val snakeDirection = ReadWriteLocation[Direction]("snakeDirection", 0x02.z)
@@ -135,6 +135,15 @@ class Easy6502Spec extends AnyFlatSpec with should.Matchers {
 
     val doc =
       asmDoc { implicit ctx =>
+        group("6502js") { implicit g =>
+          g.push(sysRandom)
+          g.push(sysLastKey)
+        }
+
+        group("snake") { implicit g =>
+          val _ = g
+        }
+
         bitField[Direction]
         mapping[AsciiValue]