From 609bc0bcd507abe06d5274ac1773aa306ab48e46 Mon Sep 17 00:00:00 2001
From: otya128 <otya128@users.noreply.github.com>
Date: Thu, 8 Dec 2016 22:32:51 +0900
Subject: [PATCH] Add VAR(expr)=expr

---
 SMILEBASIC/VM.d       | 64 +++++++++++++++++++++++++++++++++++++++++++
 SMILEBASIC/compiler.d | 14 ++++++++++
 SMILEBASIC/node.d     |  2 +-
 3 files changed, 79 insertions(+), 1 deletion(-)

diff --git a/SMILEBASIC/VM.d b/SMILEBASIC/VM.d
index a76f48a..e78e4a0 100644
--- a/SMILEBASIC/VM.d
+++ b/SMILEBASIC/VM.d
@@ -1943,3 +1943,67 @@ class SwapCode : Code
             *dp1 = num2;
     }
 }
+
+class PushVarRefExpression : Code
+{
+    Scope sc;
+    this(Scope sc)
+    {
+        this.sc = sc;
+    }
+    override void execute(VM vm)
+    {
+        Value valv;
+        vm.pop(valv);
+        auto name = valv.castString;
+
+        VMVariable vmv = VMVariable(int.min);
+        if (sc.func)
+        {
+            vmv = sc.func.variable.get(name, vmv);
+            if (vmv.index != int.min)
+            {
+                vm.push(Value(&vm.stack[vm.bp + vmv.index]));
+                return;
+            }
+        }
+        vmv = vm.currentSlot.globalTable.get(name, vmv);
+        if (vmv.index == int.min)
+        {
+            throw new UndefinedVariable();
+        }
+        vm.push(Value(&vm.currentSlot.global[vmv.index]));
+    }
+}
+
+class PushVarExpression : Code
+{
+    Scope sc;
+    this(Scope sc)
+    {
+        this.sc = sc;
+    }
+    override void execute(VM vm)
+    {
+        Value valv;
+        vm.pop(valv);
+        auto name = valv.castString;
+
+        VMVariable vmv = VMVariable(int.min);
+        if (sc.func)
+        {
+            vmv = sc.func.variable.get(name, vmv);
+            if (vmv.index != int.min)
+            {
+                vm.push(vm.stack[vm.bp + vmv.index]);
+                return;
+            }
+        }
+        vmv = vm.currentSlot.globalTable.get(name, vmv);
+        if (vmv.index == int.min)
+        {
+            throw new UndefinedVariable();
+        }
+        vm.push(vm.currentSlot.global[vmv.index]);
+    }
+}
diff --git a/SMILEBASIC/compiler.d b/SMILEBASIC/compiler.d
index 3527b6a..8ce3863 100644
--- a/SMILEBASIC/compiler.d
+++ b/SMILEBASIC/compiler.d
@@ -578,6 +578,13 @@ class Compiler
                     }
                 }
                 break;
+            case NodeType.VarRef:
+                {
+                    auto varref = cast(VarRef)exp;
+                    compileExpression(varref.expression, sc);
+                    genCode(new PushVarExpression(sc));
+                }
+                break;
             default:
                 stderr.writeln("Compile:NotImpl ", exp.type);
                 break;
@@ -628,6 +635,13 @@ class Compiler
                     }
                 }
                 break;
+            case NodeType.VarRef:
+                {
+                    auto varref = cast(VarRef)exp;
+                    compileExpression(varref.expression, sc);
+                    genCode(new PushVarRefExpression(sc));
+                }
+                break;
             default:
                 stderr.writeln("Compile:NotImpl ", exp.type);
                 break;
diff --git a/SMILEBASIC/node.d b/SMILEBASIC/node.d
index 4ceac52..84f628c 100644
--- a/SMILEBASIC/node.d
+++ b/SMILEBASIC/node.d
@@ -628,6 +628,6 @@ class VarRef : Expression
     {
         super.location = loc;
         this.type = NodeType.VarRef;
-        this.expression = expression;
+        this.expression = expr;
     }
 }