add del impl

src/compiler.h

@@ -43,7 +43,6 @@ class Compiler {
 public:
     std::unique_ptr<Parser> parser;
     bool repl_mode;
-    bool l_value;
 
     std::stack<_Code> codes;
     std::stack<Loop> loops;
@@ -466,21 +465,13 @@ public:
             throw SyntaxError(path, parser->previous, "expected an expression");
         }
 
-        // Make a "backup" of the l value before parsing next operators to
-        // reset once it done.
-        bool l_value = this->l_value;
-
-        this->l_value = precedence <= PREC_LOWEST;
         (this->*prefix)();
-
         while (rules[peek()].precedence >= precedence) {
             lexToken();
             _TokenType op = parser->previous.type;
             GrammarFn infix = rules[op].infix;
             (this->*infix)();
         }
-
-        this->l_value = l_value;
     }
 
     void keepOpcodeLine(){

src/pointer.h

@@ -7,6 +7,7 @@ class Frame;
 struct BasePointer {
     virtual PyVar get(VM*, Frame*) const = 0;
     virtual void set(VM*, Frame*, PyVar) const = 0;
+    virtual void del(VM*, Frame*) const = 0;
 };
 
 enum NameScope {
@@ -22,6 +23,7 @@ struct NamePointer : BasePointer {
 
     PyVar get(VM* vm, Frame* frame) const;
     void set(VM* vm, Frame* frame, PyVar val) const;
+    void del(VM* vm, Frame* frame) const;
 
     bool operator==(const NamePointer& other) const {
         return name == other.name && scope == other.scope;
@@ -35,6 +37,7 @@ struct AttrPointer : BasePointer {
 
     PyVar get(VM* vm, Frame* frame) const;
     void set(VM* vm, Frame* frame, PyVar val) const;
+    void del(VM* vm, Frame* frame) const;
 };
 
 struct IndexPointer : BasePointer {
@@ -44,4 +47,5 @@ struct IndexPointer : BasePointer {
 
     PyVar get(VM* vm, Frame* frame) const;
     void set(VM* vm, Frame* frame, PyVar val) const;
+    void del(VM* vm, Frame* frame) const;
 };

src/str.h

@@ -141,6 +141,7 @@ const _Str& __str__ = _Str("__str__");
 const _Str& __neg__ = _Str("__neg__");
 const _Str& __getitem__ = _Str("__getitem__");
 const _Str& __setitem__ = _Str("__setitem__");
+const _Str& __delitem__ = _Str("__delitem__");
 const _Str& __contains__ = _Str("__contains__");
 const _Str& __init__ = _Str("__init__");
 

src/vm.h

@@ -159,6 +159,10 @@ public:
                 _Pointer p = PyPointer_AS_C(frame->__pop());
                 p->set(this, frame.get(), obj);
             } break;
+            case OP_DELETE_PTR: {
+                _Pointer p = PyPointer_AS_C(frame->__pop());
+                p->del(this, frame.get());
+            } break;
             case OP_STORE_FUNCTION:
                 {
                     PyVar obj = frame->popValue(this);
@@ -587,6 +591,31 @@ void NamePointer::set(VM* vm, Frame* frame, PyVar val) const{
     }
 }
 
+void NamePointer::del(VM* vm, Frame* frame) const{
+    switch(scope) {
+        case NAME_LOCAL: {
+            if(frame->f_locals.count(name) > 0){
+                frame->f_locals.erase(name);
+            }else{
+                vm->nameError(name);
+            }
+        } break;
+        case NAME_GLOBAL:
+        {
+            if(frame->f_locals.count(name) > 0){
+                frame->f_locals.erase(name);
+            }else{
+                if(frame->f_globals->count(name) > 0){
+                    frame->f_globals->erase(name);
+                }else{
+                    vm->nameError(name);
+                }
+            }
+        } break;
+        default: UNREACHABLE();
+    }
+}
+
 PyVar AttrPointer::get(VM* vm, Frame* frame) const{
     return vm->getAttr(obj, attr->name);
 }
@@ -595,6 +624,10 @@ void AttrPointer::set(VM* vm, Frame* frame, PyVar val) const{
     vm->setAttr(obj, attr->name, val);
 }
 
+void AttrPointer::del(VM* vm, Frame* frame) const{
+    vm->_error("AttributeError", "can't delete attribute");
+}
+
 PyVar IndexPointer::get(VM* vm, Frame* frame) const{
     return vm->call(obj, __getitem__, {index});
 }
@@ -603,6 +636,10 @@ void IndexPointer::set(VM* vm, Frame* frame, PyVar val) const{
     vm->call(obj, __setitem__, {index, val});
 }
 
+void IndexPointer::del(VM* vm, Frame* frame) const{
+    vm->call(obj, __delitem__, {index});
+}
+
 /**************** Frame ****************/
 inline PyVar Frame::__deref_pointer(VM* vm, PyVar v){
     if(v->isType(vm->_tp_pointer)) v = vm->PyPointer_AS_C(v)->get(vm, this);