bridge: add ScopeFacade receiver overloads for binder callbacks

docs/embedding.md

@@ -261,14 +261,14 @@ moduleScope.eval("class Counter { extern var value: Int; extern fun inc(by: Int)
 moduleScope.bind("Counter") {
     addVar(
         name = "value",
-        get = { _, self -> self.readField(this, "value").value },
-        set = { _, self, v -> self.writeField(this, "value", v) }
+        get = { thisObj.readField(this, "value").value },
+        set = { v -> thisObj.writeField(this, "value", v) }
     )
-    addFun("inc") { _, self, args ->
+    addFun("inc") {
         val by = args.requiredArg<ObjInt>(0).value
-        val current = self.readField(this, "value").value as ObjInt
+        val current = thisObj.readField(this, "value").value as ObjInt
         val next = ObjInt(current.value + by)
-        self.writeField(this, "value", next)
+        thisObj.writeField(this, "value", next)
         next
     }
 }
@@ -303,16 +303,16 @@ moduleScope.eval("""
 moduleScope.bindObject("HostObject") {
     classData = "OK"
     init { _ -> data = 0L }
-    addFun("add") { _, _, args ->
+    addFun("add") {
         val a = args.requiredArg<ObjInt>(0).value
         val b = args.requiredArg<ObjInt>(1).value
         ObjInt.of(a + b)
     }
-    addVal("status") { _, _ -> ObjString(classData as String) }
+    addVal("status") { ObjString(classData as String) }
     addVar(
         "count",
-        get = { _, inst -> ObjInt.of((inst as ObjInstance).data as Long) },
-        set = { _, inst, value -> (inst as ObjInstance).data = (value as ObjInt).value }
+        get = { ObjInt.of((thisObj as ObjInstance).data as Long) },
+        set = { value -> (thisObj as ObjInstance).data = (value as ObjInt).value }
     )
 }
 ```
@@ -336,7 +336,7 @@ moduleScope.eval("""
 """.trimIndent())
 
 moduleScope.bindObject("HostObject") {
-    addFun("ping") { _, _, _ -> ObjInt.of(7) }
+    addFun("ping") { ObjInt.of(7) }
 }
 ```
 

lynglib/src/commonMain/kotlin/net/sergeych/lyng/bridge/ClassBridge.kt

@@ -60,12 +60,54 @@ interface ClassBridgeBinder {
     /** Register an initialization hook that runs for each instance. */
     fun init(block: suspend BridgeInstanceContext.(ScopeFacade) -> Unit)
     /** Register an initialization hook with direct access to the instance. */
+    fun initWithInstance(block: suspend ScopeFacade.() -> Unit)
+    /**
+     * Legacy initWithInstance form.
+     * Prefer [initWithInstance] with [ScopeFacade] receiver and use [ScopeFacade.thisObj].
+     */
+    @Deprecated(
+        message = "Use initWithInstance { ... } with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith("initWithInstance { block(this, thisObj) }")
+    )
     fun initWithInstance(block: suspend (ScopeFacade, Obj) -> Unit)
     /** Bind a Lyng function/member to a Kotlin implementation (requires `extern` in Lyng). */
+    fun addFun(name: String, impl: suspend ScopeFacade.() -> Obj)
+    /**
+     * Legacy addFun form.
+     * Prefer [addFun] with [ScopeFacade] receiver and use [ScopeFacade.thisObj]/[ScopeFacade.args].
+     */
+    @Deprecated(
+        message = "Use addFun(name) { ... } with ScopeFacade receiver; use thisObj/args from scope",
+        replaceWith = ReplaceWith("addFun(name) { impl(this, thisObj, args) }")
+    )
     fun addFun(name: String, impl: suspend (ScopeFacade, Obj, Arguments) -> Obj)
     /** Bind a read-only member (val/property getter) declared as `extern`. */
+    fun addVal(name: String, impl: suspend ScopeFacade.() -> Obj)
+    /**
+     * Legacy addVal form.
+     * Prefer [addVal] with [ScopeFacade] receiver and use [ScopeFacade.thisObj].
+     */
+    @Deprecated(
+        message = "Use addVal(name) { ... } with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith("addVal(name) { impl(this, thisObj) }")
+    )
     fun addVal(name: String, impl: suspend (ScopeFacade, Obj) -> Obj)
     /** Bind a mutable member (var/property getter/setter) declared as `extern`. */
+    fun addVar(
+        name: String,
+        get: suspend ScopeFacade.() -> Obj,
+        set: suspend ScopeFacade.(Obj) -> Unit
+    )
+    /**
+     * Legacy addVar form.
+     * Prefer [addVar] with [ScopeFacade] receiver and use [ScopeFacade.thisObj].
+     */
+    @Deprecated(
+        message = "Use addVar(name, get, set) with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith(
+            "addVar(name, get = { get(this, thisObj) }, set = { value -> set(this, thisObj, value) })"
+        )
+    )
     fun addVar(
         name: String,
         get: suspend (ScopeFacade, Obj) -> Obj,
@@ -234,17 +276,27 @@ private class ClassBridgeBinderImpl(
         }
     }
 
+    override fun initWithInstance(block: suspend ScopeFacade.() -> Unit) {
+        initHooks.add { scope, _ ->
+            scope.block()
+        }
+    }
+
+    @Deprecated(
+        message = "Use initWithInstance { ... } with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith("initWithInstance { block(this, thisObj) }")
+    )
     override fun initWithInstance(block: suspend (ScopeFacade, Obj) -> Unit) {
         initHooks.add { scope, inst ->
             block(scope, inst)
         }
     }
 
-    override fun addFun(name: String, impl: suspend (ScopeFacade, Obj, Arguments) -> Obj) {
+    override fun addFun(name: String, impl: suspend ScopeFacade.() -> Obj) {
         ensureTemplateNotBuilt()
         val target = findMember(name)
         val callable = ObjExternCallable.fromBridge {
-            impl(this, thisObj, args)
+            impl()
         }
         val methodId = cls.ensureMethodIdForBridge(name, target.record)
         val newRecord = target.record.copy(
@@ -255,14 +307,24 @@ private class ClassBridgeBinderImpl(
         replaceMember(target, newRecord)
     }
 
-    override fun addVal(name: String, impl: suspend (ScopeFacade, Obj) -> Obj) {
+    @Deprecated(
+        message = "Use addFun(name) { ... } with ScopeFacade receiver; use thisObj/args from scope",
+        replaceWith = ReplaceWith("addFun(name) { impl(this, thisObj, args) }")
+    )
+    override fun addFun(name: String, impl: suspend (ScopeFacade, Obj, Arguments) -> Obj) {
+        addFun(name) {
+            impl(this, thisObj, args)
+        }
+    }
+
+    override fun addVal(name: String, impl: suspend ScopeFacade.() -> Obj) {
         ensureTemplateNotBuilt()
         val target = findMember(name)
         if (target.record.isMutable) {
             throw ScriptError(Pos.builtIn, "extern val $name is mutable in class ${cls.className}")
         }
         val getter = ObjExternCallable.fromBridge {
-            impl(this, thisObj)
+            impl()
         }
         val prop = ObjProperty(name, getter, null)
         val isFieldLike = target.record.type == ObjRecord.Type.Field ||
@@ -287,10 +349,20 @@ private class ClassBridgeBinderImpl(
         replaceMember(target, newRecord)
     }
 
+    @Deprecated(
+        message = "Use addVal(name) { ... } with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith("addVal(name) { impl(this, thisObj) }")
+    )
+    override fun addVal(name: String, impl: suspend (ScopeFacade, Obj) -> Obj) {
+        addVal(name) {
+            impl(this, thisObj)
+        }
+    }
+
     override fun addVar(
         name: String,
-        get: suspend (ScopeFacade, Obj) -> Obj,
-        set: suspend (ScopeFacade, Obj, Obj) -> Unit
+        get: suspend ScopeFacade.() -> Obj,
+        set: suspend ScopeFacade.(Obj) -> Unit
     ) {
         ensureTemplateNotBuilt()
         val target = findMember(name)
@@ -298,11 +370,11 @@ private class ClassBridgeBinderImpl(
             throw ScriptError(Pos.builtIn, "extern var $name is readonly in class ${cls.className}")
         }
         val getter = ObjExternCallable.fromBridge {
-            get(this, thisObj)
+            get()
         }
         val setter = ObjExternCallable.fromBridge {
             val value = requiredArg<Obj>(0)
-            set(this, thisObj, value)
+            set(value)
             ObjVoid
         }
         val prop = ObjProperty(name, getter, setter)
@@ -328,6 +400,24 @@ private class ClassBridgeBinderImpl(
         replaceMember(target, newRecord)
     }
 
+    @Deprecated(
+        message = "Use addVar(name, get, set) with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith(
+            "addVar(name, get = { get(this, thisObj) }, set = { value -> set(this, thisObj, value) })"
+        )
+    )
+    override fun addVar(
+        name: String,
+        get: suspend (ScopeFacade, Obj) -> Obj,
+        set: suspend (ScopeFacade, Obj, Obj) -> Unit
+    ) {
+        addVar(
+            name,
+            get = { get(this, thisObj) },
+            set = { value -> set(this, thisObj, value) }
+        )
+    }
+
     fun commit() {
         if (initHooks.isNotEmpty()) {
             val target = cls.bridgeInitHooks ?: mutableListOf<suspend (ScopeFacade, ObjInstance) -> Unit>().also {
@@ -399,16 +489,26 @@ private class ObjectBridgeBinderImpl(
         }
     }
 
+    override fun initWithInstance(block: suspend ScopeFacade.() -> Unit) {
+        initHooks.add { scope, _ ->
+            scope.block()
+        }
+    }
+
+    @Deprecated(
+        message = "Use initWithInstance { ... } with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith("initWithInstance { block(this, thisObj) }")
+    )
     override fun initWithInstance(block: suspend (ScopeFacade, Obj) -> Unit) {
         initHooks.add { scope, inst ->
             block(scope, inst)
         }
     }
 
-    override fun addFun(name: String, impl: suspend (ScopeFacade, Obj, Arguments) -> Obj) {
+    override fun addFun(name: String, impl: suspend ScopeFacade.() -> Obj) {
         val target = findMember(name)
         val callable = ObjExternCallable.fromBridge {
-            impl(this, thisObj, args)
+            impl()
         }
         val methodId = cls.ensureMethodIdForBridge(name, target.record)
         val newRecord = target.record.copy(
@@ -420,13 +520,23 @@ private class ObjectBridgeBinderImpl(
         updateInstanceMember(target, newRecord)
     }
 
-    override fun addVal(name: String, impl: suspend (ScopeFacade, Obj) -> Obj) {
+    @Deprecated(
+        message = "Use addFun(name) { ... } with ScopeFacade receiver; use thisObj/args from scope",
+        replaceWith = ReplaceWith("addFun(name) { impl(this, thisObj, args) }")
+    )
+    override fun addFun(name: String, impl: suspend (ScopeFacade, Obj, Arguments) -> Obj) {
+        addFun(name) {
+            impl(this, thisObj, args)
+        }
+    }
+
+    override fun addVal(name: String, impl: suspend ScopeFacade.() -> Obj) {
         val target = findMember(name)
         if (target.record.isMutable) {
             throw ScriptError(Pos.builtIn, "extern val $name is mutable in class ${cls.className}")
         }
         val getter = ObjExternCallable.fromBridge {
-            impl(this, thisObj)
+            impl()
         }
         val prop = ObjProperty(name, getter, null)
         val isFieldLike = target.record.type == ObjRecord.Type.Field ||
@@ -452,21 +562,31 @@ private class ObjectBridgeBinderImpl(
         updateInstanceMember(target, newRecord)
     }
 
+    @Deprecated(
+        message = "Use addVal(name) { ... } with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith("addVal(name) { impl(this, thisObj) }")
+    )
+    override fun addVal(name: String, impl: suspend (ScopeFacade, Obj) -> Obj) {
+        addVal(name) {
+            impl(this, thisObj)
+        }
+    }
+
     override fun addVar(
         name: String,
-        get: suspend (ScopeFacade, Obj) -> Obj,
-        set: suspend (ScopeFacade, Obj, Obj) -> Unit
+        get: suspend ScopeFacade.() -> Obj,
+        set: suspend ScopeFacade.(Obj) -> Unit
     ) {
         val target = findMember(name)
         if (!target.record.isMutable) {
             throw ScriptError(Pos.builtIn, "extern var $name is readonly in class ${cls.className}")
         }
         val getter = ObjExternCallable.fromBridge {
-            get(this, thisObj)
+            get()
         }
         val setter = ObjExternCallable.fromBridge {
             val value = requiredArg<Obj>(0)
-            set(this, thisObj, value)
+            set(value)
             ObjVoid
         }
         val prop = ObjProperty(name, getter, setter)
@@ -493,6 +613,24 @@ private class ObjectBridgeBinderImpl(
         updateInstanceMember(target, newRecord)
     }
 
+    @Deprecated(
+        message = "Use addVar(name, get, set) with ScopeFacade receiver; use thisObj from scope",
+        replaceWith = ReplaceWith(
+            "addVar(name, get = { get(this, thisObj) }, set = { value -> set(this, thisObj, value) })"
+        )
+    )
+    override fun addVar(
+        name: String,
+        get: suspend (ScopeFacade, Obj) -> Obj,
+        set: suspend (ScopeFacade, Obj, Obj) -> Unit
+    ) {
+        addVar(
+            name,
+            get = { get(this, thisObj) },
+            set = { value -> set(this, thisObj, value) }
+        )
+    }
+
     suspend fun commit() {
         if (initHooks.isNotEmpty()) {
             val target = cls.bridgeInitHooks ?: mutableListOf<suspend (ScopeFacade, ObjInstance) -> Unit>().also {

lynglib/src/commonMain/kotlin/net/sergeych/lyng/obj/ObjKotlinIterator.kt

@@ -45,18 +45,18 @@ class ObjKotlinIterator(val iterator: Iterator<Any?>) : Obj() {
             }
             boundType = cls
             LyngClassBridge.bind(cls) {
-                addFun("next") { scope, self, _ ->
-                    when (self) {
+                addFun("next") {
+                    when (val self = thisObj) {
                         is ObjKotlinIterator -> self.iterator.next().toObj()
                         is ObjKotlinObjIterator -> self.iterator.next()
-                        else -> scope.raiseClassCastError("Expected KotlinIterator, got ${self.objClass.className}")
+                        else -> raiseClassCastError("Expected KotlinIterator, got ${self.objClass.className}")
                     }
                 }
-                addFun("hasNext") { scope, self, _ ->
-                    when (self) {
+                addFun("hasNext") {
+                    when (val self = thisObj) {
                         is ObjKotlinIterator -> self.iterator.hasNext().toObj()
                         is ObjKotlinObjIterator -> self.iterator.hasNext().toObj()
-                        else -> scope.raiseClassCastError("Expected KotlinIterator, got ${self.objClass.className}")
+                        else -> raiseClassCastError("Expected KotlinIterator, got ${self.objClass.className}")
                     }
                 }
             }

lynglib/src/commonTest/kotlin/BridgeBindingTest.kt

@@ -61,39 +61,39 @@ class BridgeBindingTest {
             init { _ ->
                 data = CounterState(0)
             }
-            addFun("add") { _, _, args ->
+            addFun("add") {
                 val a = (args.list[0] as ObjInt).value
                 val b = (args.list[1] as ObjInt).value
                 ObjInt.of(a + b)
             }
-            addVal("status") { _, _ -> ObjString(classData as String) }
+            addVal("status") { ObjString(classData as String) }
             addVar(
                 "count",
-                get = { _, instance ->
-                    val st = (instance as net.sergeych.lyng.obj.ObjInstance).data as CounterState
+                get = {
+                    val st = (thisObj as net.sergeych.lyng.obj.ObjInstance).data as CounterState
                     ObjInt.of(st.count)
                 },
-                set = { _, instance, value ->
-                    val st = (instance as net.sergeych.lyng.obj.ObjInstance).data as CounterState
+                set = { value ->
+                    val st = (thisObj as net.sergeych.lyng.obj.ObjInstance).data as CounterState
                     st.count = (value as ObjInt).value
                 }
             )
-            addFun("secret") { _, _, _ -> ObjInt.of(42) }
-            addFun("ping") { _, _, _ -> ObjInt.of(7) }
+            addFun("secret") { ObjInt.of(42) }
+            addFun("ping") { ObjInt.of(7) }
         }
 
         LyngClassBridge.bind(className = "Bar", module = "bridge.mod", importManager = im) {
-            initWithInstance { _, instance ->
-                (instance as net.sergeych.lyng.obj.ObjInstance).data = CounterState(10)
+            initWithInstance {
+                (thisObj as net.sergeych.lyng.obj.ObjInstance).data = CounterState(10)
             }
             addVar(
                 "count",
-                get = { _, instance ->
-                    val st = (instance as net.sergeych.lyng.obj.ObjInstance).data as CounterState
+                get = {
+                    val st = (thisObj as net.sergeych.lyng.obj.ObjInstance).data as CounterState
                     ObjInt.of(st.count)
                 },
-                set = { _, instance, value ->
-                    val st = (instance as net.sergeych.lyng.obj.ObjInstance).data as CounterState
+                set = { value ->
+                    val st = (thisObj as net.sergeych.lyng.obj.ObjInstance).data as CounterState
                     st.count = (value as ObjInt).value
                 }
             )
@@ -156,7 +156,7 @@ class BridgeBindingTest {
 
         val bindFailed = try {
             LyngClassBridge.bind(className = "Late", module = "bridge.late", importManager = im) {
-                addVal("status") { _, _ -> ObjString("late") }
+                addVal("status") { ObjString("late") }
             }
             false
         } catch (_: ScriptError) {
@@ -183,20 +183,20 @@ class BridgeBindingTest {
                 init { _ ->
                     data = CounterState(5)
                 }
-                addFun("add") { _, _, args ->
+                addFun("add") {
                     val a = (args.list[0] as ObjInt).value
                     val b = (args.list[1] as ObjInt).value
                     ObjInt.of(a + b)
                 }
-                addVal("status") { _, _ -> ObjString(classData as String) }
+                addVal("status") { ObjString(classData as String) }
                 addVar(
                     "count",
-                    get = { _, instance ->
-                        val st = (instance as net.sergeych.lyng.obj.ObjInstance).data as CounterState
+                    get = {
+                        val st = (thisObj as net.sergeych.lyng.obj.ObjInstance).data as CounterState
                         ObjInt.of(st.count)
                     },
-                    set = { _, instance, value ->
-                        val st = (instance as net.sergeych.lyng.obj.ObjInstance).data as CounterState
+                    set = { value ->
+                        val st = (thisObj as net.sergeych.lyng.obj.ObjInstance).data as CounterState
                         st.count = (value as ObjInt).value
                     }
                 )

notes/bridge_facade_draft.kt

@@ -146,10 +146,22 @@ interface ClassBridgeBinder {
     var classData: Any?
 
     fun init(block: suspend BridgeInstanceContext.(ScopeFacade) -> Unit)
+    fun initWithInstance(block: suspend ScopeFacade.() -> Unit)
+    @Deprecated("Use receiver-form initWithInstance and read thisObj from ScopeFacade")
     fun initWithInstance(block: suspend (ScopeFacade, Obj) -> Unit)
 
+    fun addFun(name: String, impl: suspend ScopeFacade.() -> Obj)
+    @Deprecated("Use receiver-form addFun and read thisObj/args from ScopeFacade")
     fun addFun(name: String, impl: suspend (ScopeFacade, Obj, Arguments) -> Obj)
+    fun addVal(name: String, impl: suspend ScopeFacade.() -> Obj)
+    @Deprecated("Use receiver-form addVal and read thisObj from ScopeFacade")
     fun addVal(name: String, impl: suspend (ScopeFacade, Obj) -> Obj)
+    fun addVar(
+        name: String,
+        get: suspend ScopeFacade.() -> Obj,
+        set: suspend ScopeFacade.(Obj) -> Unit
+    )
+    @Deprecated("Use receiver-form addVar and read thisObj from ScopeFacade")
     fun addVar(
         name: String,
         get: suspend (ScopeFacade, Obj) -> Obj,

notes/kotlin_bridge_binding.md

@@ -39,34 +39,34 @@ LyngClassBridge.bind(className = "Foo", module = "bridge.mod", importManager = i
         data = CounterState(0)
     }
 
-    addFun("add") { _, _, args ->
+    addFun("add") {
         val a = (args.list[0] as ObjInt).value
         val b = (args.list[1] as ObjInt).value
         ObjInt.of(a + b)
     }
 
-    addVal("status") { _, _ -> ObjString(classData as String) }
+    addVal("status") { ObjString(classData as String) }
 
     addVar(
         "count",
-        get = { _, instance ->
-            val st = (instance as ObjInstance).data as CounterState
+        get = {
+            val st = (thisObj as ObjInstance).data as CounterState
             ObjInt.of(st.count)
         },
-        set = { _, instance, value ->
-            val st = (instance as ObjInstance).data as CounterState
+        set = { value ->
+            val st = (thisObj as ObjInstance).data as CounterState
             st.count = (value as ObjInt).value
         }
     )
 
-    addFun("secret") { _, _, _ -> ObjInt.of(42) }
-    addFun("ping") { _, _, _ -> ObjInt.of(7) }
+    addFun("secret") { ObjInt.of(42) }
+    addFun("ping") { ObjInt.of(7) }
 }
 ```
 
 ## Notes
 
 - Visibility is respected by usual Lyng access rules; private extern members can be used only within class code.
-- Use `init { scope -> ... }` for receiver-style init, or `initWithInstance { scope, instance -> ... }` for explicit instance access.
+- Use `init { ... }` / `initWithInstance { ... }` with `ScopeFacade` receiver; access instance via `thisObj`.
 - `classData` and `instance.data` are Kotlin-only payloads and do not appear in Lyng reflection.
 - Binding after the first instance of a class is created throws a `ScriptError`.