From a1fb1f3cdf0509c8fc358ed79e69ed4b3b2165f9 Mon Sep 17 00:00:00 2001
From: "Flavio S. Glock" <fglock@gmail.com>
Date: Mon, 21 Oct 2024 15:19:05 +0200
Subject: [PATCH] fix code references with `&`

---
 FEATURE_MATRIX.md                             |  2 +-
 .../perlonjava/codegen/EmitterVisitor.java    | 19 +++++++++++++++----
 .../org/perlonjava/runtime/RuntimeScalar.java |  7 +++++++
 3 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/FEATURE_MATRIX.md b/FEATURE_MATRIX.md
index 9965efd..de8b749 100644
--- a/FEATURE_MATRIX.md
+++ b/FEATURE_MATRIX.md
@@ -168,7 +168,7 @@
 - ✔️   **Compound assignment operators**: Compound assignment operators are implemented.
 - ✔️   **`package` declaration**: `package BLOCK` is also supported.
 - ✔️   **Typeglob operations**: Operations like `*x = sub {}` are supported.
-- ✔️   **Code references**: Code references like `&subr` are implemented.
+- ✔️   **Code references**: Code references like `\&subr`, `\&$subname`, `\&{$subname}`, are implemented.
 - ✔️   **Special literals**: `__PACKAGE__`, `__FILE__`, `__LINE__`
 - ✔️   **`die` related operators**: `die`, `warn`, `exit` are supported.
 - ❌  **`die` related features**: `$SIG{__DIE__}`, `$SIG{__WARN__}`, `PROPAGATE` are not yet supported.
diff --git a/src/main/java/org/perlonjava/codegen/EmitterVisitor.java b/src/main/java/org/perlonjava/codegen/EmitterVisitor.java
index c226879..3bafd3c 100644
--- a/src/main/java/org/perlonjava/codegen/EmitterVisitor.java
+++ b/src/main/java/org/perlonjava/codegen/EmitterVisitor.java
@@ -886,10 +886,21 @@ private void handleCreateReference(OperatorNode node) {
                 mv.visitInsn(Opcodes.POP);
             }
         } else {
-            if (node.operand instanceof OperatorNode && ((OperatorNode) node.operand).operator.equals("&")) {
-                // System.out.println("handleCreateReference of &var");
-                //  &var is already a reference
-                node.operand.accept(this.with(RuntimeContextType.LIST));
+            if (node.operand instanceof OperatorNode operatorNode && operatorNode.operator.equals("&")) {
+                ctx.logDebug("Handle \\& " + operatorNode.operand);
+                if (operatorNode.operand instanceof OperatorNode || operatorNode.operand instanceof BlockNode) {
+                    // \&$a or \&{$a}
+                    operatorNode.operand.accept(this.with(RuntimeContextType.SCALAR));
+                    ctx.mv.visitLdcInsn(ctx.symbolTable.getCurrentPackage());
+                    ctx.mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL,
+                            "org/perlonjava/runtime/RuntimeScalar",
+                            "createCodeReference",
+                            "(Ljava/lang/String;)Lorg/perlonjava/runtime/RuntimeScalar;",
+                            false);
+                } else {
+                    // assume \&var, which is already a reference
+                    node.operand.accept(this.with(RuntimeContextType.LIST));
+                }
             } else {
                 node.operand.accept(this.with(RuntimeContextType.LIST));
                 ctx.mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "org/perlonjava/runtime/RuntimeDataProvider", "createReference", "()Lorg/perlonjava/runtime/RuntimeScalar;", true);
diff --git a/src/main/java/org/perlonjava/runtime/RuntimeScalar.java b/src/main/java/org/perlonjava/runtime/RuntimeScalar.java
index 0161e5e..dd857b0 100644
--- a/src/main/java/org/perlonjava/runtime/RuntimeScalar.java
+++ b/src/main/java/org/perlonjava/runtime/RuntimeScalar.java
@@ -898,6 +898,13 @@ public RuntimeScalar createReference() {
         return result;
     }
 
+    // Return a reference to the subroutine with this name: \&$a
+    public RuntimeScalar createCodeReference(String packageName) {
+        String name = NameNormalizer.normalizeVariableName(this.toString(), packageName);
+        System.out.println("Creating code reference: " + name + " got: " + GlobalContext.getGlobalCodeRef(name));
+        return GlobalContext.getGlobalCodeRef(name);
+    }
+
     public RuntimeScalar undefine() {
         this.type = RuntimeScalarType.UNDEF;
         return this;