diff --git a/README.md b/README.md
index f0f6b4c..e48c820 100644
--- a/README.md
+++ b/README.md
@@ -1,10 +1,10 @@
 # __Nasal Scripting Language__
 
 ```C++
-       __                _      
-    /\ \ \__ _ ___  __ _| |  
-   /  \/ / _` / __|/ _` | |    
-  / /\  / (_| \__ \ (_| | |  
+       __                _
+    /\ \ \__ _ ___  __ _| |
+   /  \/ / _` / __|/ _` | |
+  / /\  / (_| \__ \ (_| | |
   \_\ \/ \__,_|___/\__,_|_|
 ```
 
@@ -127,15 +127,15 @@ Use these commands to get version of interpreter:
 > ./nasal -v | --version
 
 ```bash
-       __                _      
-    /\ \ \__ _ ___  __ _| |  
-   /  \/ / _` / __|/ _` | |    
-  / /\  / (_| \__ \ (_| | |  
+       __                _
+    /\ \ \__ _ ___  __ _| |
+   /  \/ / _` / __|/ _` | |
+  / /\  / (_| \__ \ (_| | |
   \_\ \/ \__,_|___/\__,_|_|
 nasal interpreter ver 9.0
 thanks to : https://github.com/andyross/nasal
-code repo : https://github.com/ValKmjolnir/Nasal-Interpreter   
-code repo : https://gitee.com/valkmjolnir/Nasal-Interpreter    
+code repo : https://github.com/ValKmjolnir/Nasal-Interpreter
+code repo : https://gitee.com/valkmjolnir/Nasal-Interpreter
 lang info : http://wiki.flightgear.org/Nasal_scripting_language
 input <nasal -h> to get help .
 ```
@@ -148,7 +148,7 @@ Use these commands to get help(see more debug commands in help):
 nasal <option>
 option:
     -h, --help    | get help.
-    -v, --version | get version of nasal interpreter.  
+    -v, --version | get version of nasal interpreter.
 
 nasal <file>
 file:
@@ -157,7 +157,7 @@ file:
 nasal [options...] <file>
 option:
     -l,   --lex     | view token info.
-    -a,   --ast     | view abstract syntax tree.       
+    -a,   --ast     | view abstract syntax tree.
     -c,   --code    | view bytecode.
     -e,   --exec    | execute.
     -t,   --time    | execute and get the running time.
@@ -175,8 +175,6 @@ If your system is __`Windows`__ and you want to output unicode,please use this c
 
 > chcp 65001
 
-The interpreter's interactive mode will do this automatically,so you don't need to run this command if you use the interactive interpreter.
-
 ## __Release Notes__
 
 ### __version 8.0 release__
@@ -735,7 +733,7 @@ running time:
 |:----|:----|:----|
 |bf.nas|1100.19s||
 |mandel.nas|28.98s||
-|life.nas|0.857s(windows) 0.56(ubuntu WSL)||
+|life.nas|0.56s|0.857s(windows)|
 |ycombinator.nas|0.64s||
 |fib.nas|0.28s||
 |bfs.nas|0.156s|random result|
@@ -754,8 +752,8 @@ running time:
 |:----|:----|:----|
 |bf.nas|276.55s|great improvement|
 |mandel.nas|28.16s||
-|ycombinator.nas|0.578s||
-|life.nas|0.649s(windows) 0.2(ubuntu WSL)||
+|ycombinator.nas|0.59s||
+|life.nas|0.2s|0.649s(windows)|
 |fib.nas|0.234s|little improvement|
 |bfs.nas|0.14s|random result|
 |pi.nas|0.0625s||
diff --git a/nasal_dbg.h b/nasal_dbg.h
index 4600602..3b1e8b7 100644
--- a/nasal_dbg.h
+++ b/nasal_dbg.h
@@ -180,7 +180,7 @@ void nasal_dbg::run(
     const nasal_import& linker)
 {
     detail_info=true;
-    init(gen.get_strs(),gen.get_nums(),linker.get_file());
+    init(gen.get_strs(),gen.get_nums(),gen.get_code(),linker.get_file());
     const void* opr_table[]=
     {
         &&nop,     &&intg,     &&intl,   &&loadg,
@@ -203,7 +203,6 @@ void nasal_dbg::run(
         &&slc2,    &&mcallg,   &&mcalll, &&mupval,
         &&mcallv,  &&mcallh,   &&ret,    &&vmexit
     };
-    bytecode=gen.get_code().data();
     std::vector<const void*> code;
     for(auto& i:gen.get_code())
     {
diff --git a/nasal_gc.h b/nasal_gc.h
index f988709..94028f7 100644
--- a/nasal_gc.h
+++ b/nasal_gc.h
@@ -14,6 +14,7 @@ enum nasal_type
     vm_func,
     vm_vec,
     vm_hash,
+    vm_upval,
     vm_obj,
     vm_type_size
 };
@@ -29,18 +30,20 @@ const uint32_t increment[vm_type_size]=
     0,   // vm_nil
     0,   // vm_num
     /* gc object */
-    256, // vm_str
+    128, // vm_str
     512, // vm_func
-    512, // vm_vec
-    128, // vm_hash
+    128, // vm_vec
+    64,  // vm_hash
+    512, // vm_upval
     16   // vm_obj
 };
 
-struct nasal_vec; // vector
-struct nasal_hash;// hashmap(dict)
-struct nasal_func;// function(lambda)
-struct nasal_obj; // special objects
-struct nasal_val; // nasal_val includes gc-managed types
+struct nasal_vec;  // vector
+struct nasal_hash; // hashmap(dict)
+struct nasal_func; // function(lambda)
+struct nasal_upval;// upvalue
+struct nasal_obj;  // special objects
+struct nasal_val;  // nasal_val includes gc-managed types
 
 struct nasal_ref
 {
@@ -78,6 +81,7 @@ struct nasal_ref
     inline nasal_vec*   vec ();
     inline nasal_hash*  hash();
     inline nasal_func*  func();
+    inline nasal_upval& upval();
     inline nasal_obj*   obj ();
 };
 
@@ -113,6 +117,17 @@ struct nasal_func
     void clear();
 };
 
+struct nasal_upval
+{
+    bool onstk;
+    nasal_ref* stk;
+    std::vector<nasal_ref> elems;
+
+    nasal_upval(){onstk=true;stk=nullptr;}
+    nasal_ref& operator[](const int);
+    void clear(){onstk=true;elems.clear();}
+};
+
 struct nasal_obj
 {
     uint32_t type;
@@ -135,6 +150,7 @@ struct nasal_val
         nasal_vec*   vec;
         nasal_hash*  hash;
         nasal_func*  func;
+        nasal_upval* upval;
         nasal_obj*   obj;
     }ptr;
 
@@ -241,6 +257,13 @@ void nasal_func::clear()
     keys.clear();
 }
 
+nasal_ref& nasal_upval::operator[](const int index)
+{
+    if(onstk)
+        return stk[index];
+    return elems[index];
+}
+
 nasal_val::nasal_val(uint8_t val_type)
 {
     mark=GC_COLLECTED;
@@ -248,11 +271,12 @@ nasal_val::nasal_val(uint8_t val_type)
     unmut=0;
     switch(val_type)
     {
-        case vm_str:  ptr.str=new std::string; break;
-        case vm_vec:  ptr.vec=new nasal_vec;   break;
-        case vm_hash: ptr.hash=new nasal_hash; break;
-        case vm_func: ptr.func=new nasal_func; break;
-        case vm_obj:  ptr.obj=new nasal_obj;   break;
+        case vm_str:  ptr.str=new std::string;  break;
+        case vm_vec:  ptr.vec=new nasal_vec;    break;
+        case vm_hash: ptr.hash=new nasal_hash;  break;
+        case vm_func: ptr.func=new nasal_func;  break;
+        case vm_upval:ptr.upval=new nasal_upval;break;
+        case vm_obj:  ptr.obj=new nasal_obj;    break;
     }
 }
 nasal_val::~nasal_val()
@@ -263,6 +287,7 @@ nasal_val::~nasal_val()
         case vm_vec:  delete ptr.vec;  break;
         case vm_hash: delete ptr.hash; break;
         case vm_func: delete ptr.func; break;
+        case vm_upval:delete ptr.upval;break;
         case vm_obj:  delete ptr.obj;  break;
     }
     type=vm_nil;
@@ -293,14 +318,15 @@ void nasal_ref::print()
         case vm_obj:  std::cout<<"<object>";    break;
     }
 }
-inline uint32_t     nasal_ref::ret (){return value.ret;            }
-inline int64_t&     nasal_ref::cnt (){return value.cnt;            }
-inline double&      nasal_ref::num (){return value.num;            }
-inline std::string* nasal_ref::str (){return value.gcobj->ptr.str; }
-inline nasal_vec*   nasal_ref::vec (){return value.gcobj->ptr.vec; }
-inline nasal_hash*  nasal_ref::hash(){return value.gcobj->ptr.hash;}
-inline nasal_func*  nasal_ref::func(){return value.gcobj->ptr.func;}
-inline nasal_obj*   nasal_ref::obj (){return value.gcobj->ptr.obj; }
+inline uint32_t     nasal_ref::ret  (){return value.ret;              }
+inline int64_t&     nasal_ref::cnt  (){return value.cnt;              }
+inline double&      nasal_ref::num  (){return value.num;              }
+inline std::string* nasal_ref::str  (){return value.gcobj->ptr.str;   }
+inline nasal_vec*   nasal_ref::vec  (){return value.gcobj->ptr.vec;   }
+inline nasal_hash*  nasal_ref::hash (){return value.gcobj->ptr.hash;  }
+inline nasal_func*  nasal_ref::func (){return value.gcobj->ptr.func;  }
+inline nasal_upval& nasal_ref::upval(){return *value.gcobj->ptr.upval;}
+inline nasal_obj*   nasal_ref::obj  (){return value.gcobj->ptr.obj;   }
 
 const uint32_t STACK_MAX_DEPTH=8191;
 const nasal_ref zero={vm_num,(double)0};
@@ -355,6 +381,9 @@ void nasal_gc::mark()
                 for(auto& i:tmp.func()->upvalue)
                     bfs.push(i);
                 break;
+            case vm_upval:
+                for(auto& i:tmp.upval().elems)
+                    bfs.push(i);
         }
     }
 }
@@ -366,11 +395,12 @@ void nasal_gc::sweep()
         {
             switch(i->type)
             {
-                case vm_str: i->ptr.str->clear();       break;
-                case vm_vec: i->ptr.vec->elems.clear(); break;
-                case vm_hash:i->ptr.hash->elems.clear();break;
-                case vm_func:i->ptr.func->clear();      break;
-                case vm_obj: i->ptr.obj->clear();       break;
+                case vm_str:  i->ptr.str->clear();       break;
+                case vm_vec:  i->ptr.vec->elems.clear(); break;
+                case vm_hash: i->ptr.hash->elems.clear();break;
+                case vm_func: i->ptr.func->clear();      break;
+                case vm_upval:i->ptr.upval->clear();     break;
+                case vm_obj:  i->ptr.obj->clear();       break;
             }
             free_list[i->type].push(i);
             i->mark=GC_COLLECTED;
@@ -416,9 +446,10 @@ void nasal_gc::clear()
 void nasal_gc::info()
 {
     const char* name[]={
-        "null","cnt ","ret ",
-        "nil ","num ","str ",
-        "func","vec ","hash","obj "
+        "null ","cnt  ","ret  ",
+        "nil  ","num  ","str  ",
+        "func ","vec  ","hash ",
+        "upval","obj  "
     };
     std::cout<<"\ngarbage collector info:\n";
     for(uint8_t i=vm_str;i<vm_type_size;++i)
diff --git a/nasal_vm.h b/nasal_vm.h
index 156cba7..0e96d21 100644
--- a/nasal_vm.h
+++ b/nasal_vm.h
@@ -24,6 +24,7 @@ protected:
     void init(
         const std::vector<std::string>&,
         const std::vector<double>&,
+        const std::vector<opcode>&,
         const std::vector<std::string>&);
     /* debug functions */
     bool detail_info;
@@ -126,11 +127,13 @@ public:
 void nasal_vm::init(
     const std::vector<std::string>& strs,
     const std::vector<double>&      nums,
+    const std::vector<opcode>&      code,
     const std::vector<std::string>& filenames)
 {
     gc.init(strs);
     num_table=nums.data();
     str_table=strs.data();
+    bytecode=code.data();
     files=filenames.data();
     files_size=filenames.size();
     /* set canary and program counter */
@@ -339,11 +342,10 @@ inline void nasal_vm::opr_loadg()
 inline void nasal_vm::opr_loadl()
 {
     lstk.top()[imm[pc]]=(gc.top--)[0];
-    //gc.local.back().vec()->elems[imm[pc]]=(gc.top--)[0];
 }
 inline void nasal_vm::opr_loadu()
 {
-    fstk.top()->upvalue[(imm[pc]>>16)&0xffff].vec()->elems[imm[pc]&0xffff]=(gc.top--)[0];
+    fstk.top()->upvalue[(imm[pc]>>16)&0xffff].upval()[imm[pc]&0xffff]=(gc.top--)[0];
 }
 inline void nasal_vm::opr_pnum()
 {
@@ -383,12 +385,10 @@ inline void nasal_vm::opr_newf()
     if(!lstk.empty())
     {
         func->upvalue=fstk.top()->upvalue;
-        nasal_ref upval=(gc.upvalue.back().type==vm_nil)?gc.alloc(vm_vec):gc.upvalue.back();
+        nasal_ref upval=(gc.upvalue.back().type==vm_nil)?gc.alloc(vm_upval):gc.upvalue.back();
+        upval.upval().stk=lstk.top();
         func->upvalue.push_back(upval);
         gc.upvalue.back()=upval;
-        auto& vec=upval.vec()->elems;
-        for(uint32_t i=0;i<fstk.top()->lsize;++i)
-            vec.push_back(lstk.top()[i]);
     }
 }
 inline void nasal_vm::opr_happ()
@@ -601,7 +601,7 @@ inline void nasal_vm::opr_calll()
 }
 inline void nasal_vm::opr_upval()
 {
-    (++gc.top)[0]=fstk.top()->upvalue[(imm[pc]>>16)&0xffff].vec()->elems[imm[pc]&0xffff];
+    (++gc.top)[0]=fstk.top()->upvalue[(imm[pc]>>16)&0xffff].upval()[imm[pc]&0xffff];
 }
 inline void nasal_vm::opr_callv()
 {
@@ -801,7 +801,7 @@ inline void nasal_vm::opr_mcalll()
 }
 inline void nasal_vm::opr_mupval()
 {
-    mem_addr=&fstk.top()->upvalue[(imm[pc]>>16)&0xffff].vec()->elems[imm[pc]&0xffff];
+    mem_addr=&(fstk.top()->upvalue[(imm[pc]>>16)&0xffff].upval()[imm[pc]&0xffff]);
     (++gc.top)[0]=mem_addr[0];
 }
 inline void nasal_vm::opr_mcallv()
@@ -852,17 +852,26 @@ inline void nasal_vm::opr_ret()
     // +-----------------+
     // | local scope     |
     // +-----------------+ <- local pointer stored in lstk
-    // | called function | <- funct is set on stack because gc may mark it
+    // | called function | <- func is stored on stack because gc may mark it
     // +-----------------+
     nasal_ref ret=gc.top[0];
     pc=gc.top[-1].ret();
 
     gc.top=lstk.top()-1;
-    lstk.pop();
 
     gc.top[0].func()->local[0]={vm_nil,nullptr}; // get func and set 'me' to nil
     gc.top[0]=ret; // rewrite func with returned value
 
+    if(gc.upvalue.back().type==vm_upval) // synchronize upvalue
+    {
+        auto& upval=gc.upvalue.back().upval();
+        auto local=lstk.top();
+        auto size=fstk.top()->lsize;
+        upval.onstk=false;
+        for(uint32_t i=0;i<size;++i)
+            upval.elems.push_back(local[i]);
+    }
+    lstk.pop();
     fstk.pop();
     gc.upvalue.pop_back();
 }
@@ -873,7 +882,7 @@ void nasal_vm::run(
     const bool detail)
 {
     detail_info=detail;
-    init(gen.get_strs(),gen.get_nums(),linker.get_file());
+    init(gen.get_strs(),gen.get_nums(),gen.get_code(),linker.get_file());
     uint64_t count[op_exit+1]={0};
     const void* opr_table[]=
     {
@@ -897,7 +906,6 @@ void nasal_vm::run(
         &&slc2,    &&mcallg,   &&mcalll, &&mupval,
         &&mcallv,  &&mcallh,   &&ret,    &&vmexit
     };
-    bytecode=gen.get_code().data();
     std::vector<const void*> code;
     for(auto& i:gen.get_code())
     {
@@ -985,7 +993,7 @@ callv:   exec_opnodie(opr_callv   ,op_callv   ); // -0
 callvi:  exec_opnodie(opr_callvi  ,op_callvi  ); // -0
 callh:   exec_opnodie(opr_callh   ,op_callh   ); // -0
 callfv:  exec_opnodie(opr_callfv  ,op_callfv  ); // check in the function
-callfh:  exec_opnodie(opr_callfh  ,op_callfh  ); // -0 call this will push one hash
+callfh:  exec_opnodie(opr_callfh  ,op_callfh  ); // check in the function
 callb:   exec_opnodie(opr_callb   ,op_callb   ); // -0
 slcbegin:exec_operand(opr_slcbegin,op_slcbegin); // +1
 slcend:  exec_opnodie(opr_slcend  ,op_slcend  ); // -1