Proper implementation of is_callback() & is_callable(). First one only performs a check if variable type is callback, while the second checks if function exists and if can be called.

engine/api.c

@@ -1937,6 +1937,13 @@ int ph7_value_is_callable(ph7_value *pVal) {
 	rc = PH7_VmIsCallable(pVal->pVm, pVal, FALSE);
 	return rc;
 }
+/*
+ * [CAPIREF: ph7_value_is_callback()]
+ * Please refer to the official documentation for function purpose and expected parameters.
+ */
+int ph7_value_is_callback(ph7_value *pVal) {
+	return (pVal->iFlags & MEMOBJ_CALL) ? TRUE : FALSE;
+}
 /*
  * [CAPIREF: ph7_value_is_scalar()]
  * Please refer to the official documentation for function purpose and expected parameters.
@@ -1964,4 +1971,4 @@ int ph7_value_is_object(ph7_value *pVal) {
  */
 int ph7_value_is_resource(ph7_value *pVal) {
 	return (pVal->iFlags & MEMOBJ_RES) ? TRUE : FALSE;
-}
+}