adopt yyw02's idea

src/obj.h

@@ -18,6 +18,8 @@ class CodeObject;
 class BasePointer;
 class VM;
 
+class PkExportedResource {};
+
 typedef std::shared_ptr<PyObject> PyVar;
 typedef PyVar PyVarOrNull;
 

src/pocketpy.h

@@ -547,17 +547,10 @@ void __addModuleSys(VM* vm){
     vm->setAttr(mod, "version", vm->PyStr(PK_VERSION));
 }
 
-enum ExportType {
-    PKPY_VM,
-    PKPY_REPL
-};
-static std::unordered_map<void*, ExportType> __pkpy_allocations;
-
 extern "C" {
     __EXPORT
     VM* pkpy_new_vm(PrintFn _stdout, PrintFn _stderr){
         VM* vm = new VM();
-        __pkpy_allocations[vm] = PKPY_VM;
         __initializeBuiltinFunctions(vm);
         vm->_stdout = _stdout;
         vm->_stderr = _stderr;
@@ -572,14 +565,8 @@ extern "C" {
     }
 
     __EXPORT
-    bool pkpy_delete(void* p){
-        auto it = __pkpy_allocations.find(p);
-        if(it == __pkpy_allocations.end()) return false;
-        switch(it->second){
-            case PKPY_VM: delete (VM*)p; __pkpy_allocations.erase(it); return true;
-            case PKPY_REPL: delete (REPL*)p; __pkpy_allocations.erase(it); return true;
-        }
-        return false;
+    void pkpy_delete(PkExportedResource* p){
+        delete p;
     }
 
     __EXPORT
@@ -590,9 +577,7 @@ extern "C" {
 
     __EXPORT
     REPL* pkpy_new_repl(VM* vm, bool use_prompt){
-        REPL* repl = new REPL(vm, use_prompt);
-        __pkpy_allocations[repl] = PKPY_REPL;
-        return repl;
+        return new REPL(vm, use_prompt);
     }
 
     __EXPORT

src/repl.h

@@ -3,7 +3,7 @@
 #include "compiler.h"
 #include "vm.h"
 
-class REPL {
+class REPL: public PkExportedResource {
     int need_more_lines = 0;
     std::string buffer;
     CompileMode mode;

src/vm.h

@@ -44,7 +44,7 @@
 
 typedef void(*PrintFn)(const VM*, const char*);
 
-class VM{
+class VM: public PkExportedResource{
 private:
     std::stack< std::unique_ptr<Frame> > callstack;
     PyVarDict _modules;       // 3rd modules