diff --git a/main.cpp b/main.cpp
index f79af204..105796cc 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,7 +1,5 @@
 #include "nasal.h"
 
-nasal_vm vm;
-
 void help_interact()
 {
 	std::cout
@@ -31,7 +29,7 @@ void help_cmd()
 void info()
 {
 	std::cout
-	<<">> Nasal interpreter ver 6.5 efficient gc test .\n"
+	<<">> Nasal interpreter ver 6.5.\n"
 	<<">> Thanks to https://github.com/andyross/nasal\n"
 	<<">> Code: https://github.com/ValKmjolnir/Nasal-Interpreter\n"
 	<<">> Code: https://gitee.com/valkmjolnir/Nasal-Interpreter\n"
@@ -60,6 +58,7 @@ void execute(std::string& file,std::string& command)
 	nasal_parse   parse;
 	nasal_import  import;
 	nasal_codegen codegen;
+	nasal_vm      vm;
 	lexer.openfile(file);
 	lexer.scanner();
 	if(lexer.get_error())
@@ -153,7 +152,7 @@ int main(int argc,const char* argv[])
 	else if(argc==2 && (!strcmp(argv[1],"-v") || !strcmp(argv[1],"-version")))
 	{
 		logo();
-		std::cout<<"Nasal interpreter ver 6.5 efficient gc test\n";
+		std::cout<<"Nasal interpreter ver 6.5\n";
 	}
 	else if(argc==2 && (!strcmp(argv[1],"-h") || !strcmp(argv[1],"-help")))
 		help_cmd();
diff --git a/nasal_ast.h b/nasal_ast.h
index 90fbbce2..7051346c 100644
--- a/nasal_ast.h
+++ b/nasal_ast.h
@@ -57,10 +57,12 @@ class nasal_ast
     nasal_ast(){line=0;type=ast_null;}
     nasal_ast(int l,int t){line=l;type=t;}
     nasal_ast(const nasal_ast&);
-    nasal_ast&  operator=(const nasal_ast&);
+    nasal_ast(nasal_ast&&);
+    nasal_ast& operator=(const nasal_ast&);
+    nasal_ast& operator=(nasal_ast&&);
     void   print_ast(int);
     void   clear();
-    void   add_child(nasal_ast ast){children.push_back(ast);}
+    void   add_child(nasal_ast&& ast){children.push_back(std::move(ast));}
     void   set_line(int l){line=l;}
     void   set_type(int t){type=t;}
     void   set_str(std::string& s){str=s;}
@@ -82,6 +84,16 @@ nasal_ast::nasal_ast(const nasal_ast& tmp)
     return;
 }
 
+nasal_ast::nasal_ast(nasal_ast&& tmp)
+{
+    line=tmp.line;
+    type=tmp.type;
+    str.swap(tmp.str);
+    num =tmp.num;
+    children.swap(tmp.children);
+    return;
+}
+
 nasal_ast& nasal_ast::operator=(const nasal_ast& tmp)
 {
     line=tmp.line;
@@ -92,6 +104,16 @@ nasal_ast& nasal_ast::operator=(const nasal_ast& tmp)
     return *this;
 }
 
+nasal_ast& nasal_ast::operator=(nasal_ast&& tmp)
+{
+    line=tmp.line;
+    type=tmp.type;
+    str.swap(tmp.str);
+    num=tmp.num;
+    children.swap(tmp.children);
+    return *this;
+}
+
 void nasal_ast::clear()
 {
     line=0;
@@ -104,11 +126,10 @@ void nasal_ast::clear()
 
 void nasal_ast::print_ast(int depth)
 {
-    std::string indentation="";
     for(int i=0;i<depth;++i)
-        indentation+="|  ";
-    std::cout<<indentation<<ast_name[type];
-    if(type==ast_str || type==ast_id || type==ast_dynamic_id || type==ast_callh)
+        std::cout<<"|  ";
+    std::cout<<ast_name[type];
+    if(type==ast_str || type==ast_id || type==ast_default_arg || type==ast_dynamic_id || type==ast_callh)
         std::cout<<":"<<str;
     else if(type==ast_num)
         std::cout<<":"<<num;
diff --git a/nasal_codegen.h b/nasal_codegen.h
index 3d69d86f..4d827252 100644
--- a/nasal_codegen.h
+++ b/nasal_codegen.h
@@ -365,8 +365,8 @@ void nasal_codegen::func_gen(nasal_ast& ast)
         }
         else if(tmp.get_type()==ast_default_arg)
         {
-            calc_gen(tmp.get_children()[1]);
-            std::string& str=tmp.get_children()[0].get_str();
+            calc_gen(tmp.get_children()[0]);
+            std::string& str=tmp.get_str();
             regist_string(str);
             add_sym(str);
             gen(op_defpara,string_table[str]);
diff --git a/nasal_import.h b/nasal_import.h
index 52f651b5..a6652da2 100644
--- a/nasal_import.h
+++ b/nasal_import.h
@@ -12,7 +12,7 @@ class nasal_import
     void die(std::string&,const char*);
     bool check_import(nasal_ast&);
     bool check_exist(std::string&);
-    void linker(nasal_ast&,nasal_ast&);
+    void linker(nasal_ast&,nasal_ast&&);
     nasal_ast file_import(nasal_ast&);
     nasal_ast load(nasal_ast&);
 public:
@@ -51,21 +51,21 @@ only this kind of node can be recognized as 'import':
     return true;
 }
 
-bool nasal_import::check_exist(std::string& filename)
+bool nasal_import::check_exist(std::string& file)
 {
     // avoid importing the same file
     for(auto& fname:filename_table)
-        if(filename==fname)
+        if(file==fname)
             return true;
-    filename_table.push_back(filename);
+    filename_table.push_back(file);
     return false;
 }
 
-void nasal_import::linker(nasal_ast& root,nasal_ast& add_root)
+void nasal_import::linker(nasal_ast& root,nasal_ast&& add_root)
 {
     // add children of add_root to the back of root
     for(auto& i:add_root.get_children())
-        root.add_child(i);
+        root.add_child(std::move(i));
     return;
 }
 
@@ -75,7 +75,7 @@ nasal_ast nasal_import::file_import(nasal_ast& node)
     nasal_ast tmp(0,ast_root);
 
     // get filename and set node to ast_null
-    std::string& filename=node.get_children()[1].get_children()[0].get_str();
+    std::string filename=node.get_children()[1].get_children()[0].get_str();
     node.clear();
 
     // avoid infinite loading loop
@@ -98,7 +98,7 @@ nasal_ast nasal_import::file_import(nasal_ast& node)
         die(filename,"parser");
         return tmp;
     }
-    tmp=import_par.get_root();
+    tmp=std::move(import_par.get_root());
     import_par.get_root().clear();
     // check if tmp has 'import'
     return load(tmp);
@@ -109,14 +109,9 @@ nasal_ast nasal_import::load(nasal_ast& root)
     nasal_ast new_root(0,ast_root);
     for(auto& i:root.get_children())
         if(check_import(i))
-        {
-            nasal_ast tmp=file_import(i);
-            // add tmp to the back of new_root
-            linker(new_root,tmp);
-        }
+            linker(new_root,file_import(i));
     // add root to the back of new_root
-    linker(new_root,root);
-    // oops,i think it is not efficient if the root is too ... large?
+    linker(new_root,std::move(root));
     return new_root;
 }
 
diff --git a/nasal_parse.h b/nasal_parse.h
index b55a4e24..ebb6d320 100644
--- a/nasal_parse.h
+++ b/nasal_parse.h
@@ -48,7 +48,7 @@ class nasal_parse
     std::vector<token> error_token;
     int in_function; // count when generating function block,used to check return-expression
     int in_loop;     // count when generating loop block,used to check break/continue-expression
-    void die(int,std::string);
+    void die(int,std::string&&);
     void match(int type,const char* err_info="");
     bool check_comma(int*);
     bool check_multi_def();
@@ -140,7 +140,7 @@ void nasal_parse::main_process()
     <<"check \'(\',\'[\',\'{\',\')\',\']\',\'}\' match or not.\n";
     return;
 }
-void nasal_parse::die(int line,std::string info)
+void nasal_parse::die(int line,std::string&& info)
 {
     ++error;
     std::cout<<">> [parse] line "<<line<<": "<<info<<".\n";
@@ -378,21 +378,21 @@ nasal_ast nasal_parse::args_gen()
             nasal_ast special_arg(tok_list[ptr].line,ast_null);
             if(tok_list[ptr].type==tok_eq)
             {
-                special_arg.add_child(tmp);
                 match(tok_eq);
-                special_arg.add_child(calc());
+                special_arg=std::move(tmp);
                 special_arg.set_type(ast_default_arg);
+                special_arg.add_child(calc());
             }
             else
             {
                 match(tok_ellipsis);
-                special_arg=tmp;
+                special_arg=std::move(tmp);
                 special_arg.set_type(ast_dynamic_id);
             }
-            node.add_child(special_arg);
+            node.add_child(std::move(special_arg));
         }
         else
-            node.add_child(tmp);
+            node.add_child(std::move(tmp));
         if(tok_list[ptr].type==tok_comma)
             match(tok_comma);
         else if(tok_list[ptr].type==tok_id)// first set of identifier
@@ -407,9 +407,9 @@ nasal_ast nasal_parse::args_gen()
     {
         switch(tmp.get_type())
         {
-            case ast_id:          args_format+="val";break;
-            case ast_default_arg: args_format+="val=scalar";break;
-            case ast_dynamic_id:  args_format+="val...";break;
+            case ast_id:          args_format+=tmp.get_str();break;
+            case ast_default_arg: args_format+=tmp.get_str()+"=val";break;
+            case ast_dynamic_id:  args_format+=tmp.get_str()+"...";break;
         }
         args_format+=",)"[&tmp==&node.get_children().back()];
     }
@@ -433,7 +433,7 @@ nasal_ast nasal_parse::args_gen()
         {
             case ast_dynamic_id:
             case ast_id:         new_name=tmp.get_str();break;
-            case ast_default_arg:new_name=tmp.get_children()[0].get_str();break;
+            case ast_default_arg:new_name=tmp.get_str();break;
         }
         if(argname_table.count(new_name))
             die(tmp.get_line(),"parameter's name repeats: "+new_name);
@@ -518,21 +518,21 @@ nasal_ast nasal_parse::calc()
         // trinocular calculation
         nasal_ast tmp(tok_list[ptr].line,ast_trino);
         match(tok_quesmark);
-        tmp.add_child(node);
+        tmp.add_child(std::move(node));
         tmp.add_child(calc());
         match(tok_colon);
         tmp.add_child(calc());
-        node=tmp;
+        node=std::move(tmp);
     }
     else if(tok_eq<=tok_list[ptr].type && tok_list[ptr].type<=tok_lnkeq)
     {
         check_memory_reachable(node);
         // tok_eq~tok_lnkeq is 37 to 42,ast_equal~ast_lnkeq is 21~26
         nasal_ast tmp(tok_list[ptr].line,tok_list[ptr].type-tok_eq+ast_equal);
-        tmp.add_child(node);
+        tmp.add_child(std::move(node));
         match(tok_list[ptr].type);
         tmp.add_child(calc());
-        node=tmp;
+        node=std::move(tmp);
     }
     return node;
 }
@@ -542,10 +542,10 @@ nasal_ast nasal_parse::or_expr()
     while(tok_list[ptr].type==tok_or)
     {
         nasal_ast tmp(tok_list[ptr].line,ast_or);
-        tmp.add_child(node);
+        tmp.add_child(std::move(node));
         match(tok_or);
         tmp.add_child(and_expr());
-        node=tmp;
+        node=std::move(tmp);
     }
     return node;
 }
@@ -555,10 +555,10 @@ nasal_ast nasal_parse::and_expr()
     while(tok_list[ptr].type==tok_and)
     {
         nasal_ast tmp(tok_list[ptr].line,ast_and);
-        tmp.add_child(node);
+        tmp.add_child(std::move(node));
         match(tok_and);
         tmp.add_child(cmp_expr());
-        node=tmp;
+        node=std::move(tmp);
     }
     return node;
 }
@@ -569,10 +569,10 @@ nasal_ast nasal_parse::cmp_expr()
     {
         // tok_cmpeq~tok_geq is 43~48,ast_cmpeq~ast_geq is 27~32
         nasal_ast tmp(tok_list[ptr].line,tok_list[ptr].type-tok_cmpeq+ast_cmpeq);
-        tmp.add_child(node);
+        tmp.add_child(std::move(node));
         match(tok_list[ptr].type);
         tmp.add_child(additive_expr());
-        node=tmp;
+        node=std::move(tmp);
     }
     return node;
 }
@@ -588,10 +588,10 @@ nasal_ast nasal_parse::additive_expr()
             case tok_sub:  tmp.set_type(ast_sub);  break;
             case tok_link: tmp.set_type(ast_link); break;
         }
-        tmp.add_child(node);
+        tmp.add_child(std::move(node));
         match(tok_list[ptr].type);
         tmp.add_child(multive_expr());
-        node=tmp;
+        node=std::move(tmp);
     }
     return node;
 }
@@ -601,10 +601,10 @@ nasal_ast nasal_parse::multive_expr()
     while(tok_list[ptr].type==tok_mult || tok_list[ptr].type==tok_div)
     {
         nasal_ast tmp(tok_list[ptr].line,tok_list[ptr].type-tok_mult+ast_mult);
-        tmp.add_child(node);
+        tmp.add_child(std::move(node));
         match(tok_list[ptr].type);
         tmp.add_child((tok_list[ptr].type==tok_sub || tok_list[ptr].type==tok_not)?unary():scalar());
-        node=tmp;
+        node=std::move(tmp);
     }
     return node;
 }
@@ -667,11 +667,10 @@ nasal_ast nasal_parse::scalar()
     }
     if(is_call(tok_list[ptr].type))
     {
-        nasal_ast tmp=node;
-        node.clear();
+        nasal_ast tmp=std::move(node);
         node.set_line(tok_list[ptr].line);
         node.set_type(ast_call);
-        node.add_child(tmp);
+        node.add_child(std::move(tmp));
     }
     while(is_call(tok_list[ptr].type))
         node.add_child(call_scalar());
@@ -744,9 +743,9 @@ nasal_ast nasal_parse::subvec()
     {
         nasal_ast tmp(node.get_line(),ast_subvec);
         match(tok_colon);
-        tmp.add_child(node);
+        tmp.add_child(std::move(node));
         tmp.add_child((tok_list[ptr].type==tok_comma || tok_list[ptr].type==tok_rbracket)?nil_gen():calc());
-        node=tmp;
+        node=std::move(tmp);
     }
     return node;
 }
@@ -905,7 +904,7 @@ nasal_ast nasal_parse::for_loop()
     match(tok_semi,"expected \';\' in for(;;)");
     // conditional expression
     if(tok_list[ptr].type==tok_eof)
-        die(error_line,"expected conditional expression");
+        die(error_line,"expected conditional expr");
     if(tok_list[ptr].type==tok_semi)
         node.add_child(null_node_gen());
     else
@@ -976,7 +975,7 @@ nasal_ast nasal_parse::conditional()
     tmp.add_child(calc());
     match(tok_rcurve);
     tmp.add_child(exprs_gen());
-    node.add_child(tmp);
+    node.add_child(std::move(tmp));
     // end of if-expression
     while(tok_list[ptr].type==tok_elsif)
     {
@@ -986,14 +985,14 @@ nasal_ast nasal_parse::conditional()
         tmp.add_child(calc());
         match(tok_rcurve);
         tmp.add_child(exprs_gen());
-        node.add_child(tmp);
+        node.add_child(std::move(tmp));
     }
     if(tok_list[ptr].type==tok_else)
     {
         nasal_ast tmp(tok_list[ptr].line,ast_else);
         match(tok_else);
         tmp.add_child(exprs_gen());
-        node.add_child(tmp);
+        node.add_child(std::move(tmp));
     }
     return node;
 }
diff --git a/test/ascii-art.nas b/test/ascii-art.nas
index bad2dbea..94714ad5 100644
--- a/test/ascii-art.nas
+++ b/test/ascii-art.nas
@@ -53,9 +53,9 @@ var curve1=func()
     var shadow=["░","▒","▓","█","▀","▄","▐","▌"];
     rand(100);
     var s="";
-    for(var i=0;i<25;i+=1)
+    for(var i=0;i<10;i+=1)
     {
-        for(var j=0;j<100;j+=1)
+        for(var j=0;j<40;j+=1)
             s~=shadow[int(8*rand())];
         s~='\n';
     }
@@ -66,28 +66,15 @@ var curve2=func()
     var table=["╚","═","╝","╔","║","╗"];
     rand(100);
     var s="";
-    for(var i=0;i<25;i+=1)
+    for(var i=0;i<10;i+=1)
     {
-        for(var j=0;j<100;j+=1)
+        for(var j=0;j<40;j+=1)
             s~=table[int(6*rand())];
         s~='\n';
     }
     print(s);
 }
 var curve3=func()
-{
-    var block=["░░","▒▒","▓▓","██","▀▀","▄▄","▄▀","▀▄","▐▐","▌▌"];
-    rand(100);
-    var s="";
-    for(var i=0;i<25;i+=1)
-    {
-        for(var j=0;j<50;j+=1)
-            s~=block[int(10*rand())];
-        s~='\n';
-    }
-    print(s);
-}
-var curve4=func()
 {
     var s=["","","","","",""];
     var cnt=0;
@@ -108,12 +95,12 @@ var curve4=func()
     }
     return;
 }
-var curve5=func()
+var curve4=func()
 {
-    for(var loop=0;loop<100;loop+=1)
+    var arr=[0,1,2,3,4,5,6,7,8,0,1,2,3,4,5,6,7,8,0,1,2,3,4,5,6,7,8];
+    for(var loop=0;loop<10;loop+=1)
     {
-        var arr=[0,1,2,3,4,5,6,7,8,0,1,2,3,4,5,6,7,8];
-        for(var i=17;i>=0;i-=1)
+        for(var i=26;i>=0;i-=1)
         {
             var rand_index=int(i*rand());
             (arr[i],arr[rand_index])=(arr[rand_index],arr[i]);
@@ -128,9 +115,8 @@ var curve5=func()
     return;
 }
 trans_ttf("just for test");
-trans_ttf("ValKmjolnir");
+trans_ttf(" ValKmjolnir ");
 curve1();
 curve2();
 curve3();
-curve4();
-curve5();
\ No newline at end of file
+curve4();
\ No newline at end of file
diff --git a/test/auto_crash.nas b/test/auto_crash.nas
index e13c864b..f5c49d23 100644
--- a/test/auto_crash.nas
+++ b/test/auto_crash.nas
@@ -1,4 +1,6 @@
 # Road check and auto pilot by ValKmjolnir
+import("lib.nas");
+import("props.nas");
 var dt=0.01;
 var intergral=0;
 var derivative=0;
diff --git a/test/bf.nas b/test/bf.nas
index 69f6157e..14780c56 100644
--- a/test/bf.nas
+++ b/test/bf.nas
@@ -171,7 +171,7 @@ var bf=func(program)
         var c=chr(program[i]);
         if(c=='+' or c=='-')
         {
-            append(code,add);
+            append(code,func_table[add]);
             append(inum,0);
             for(;i<len;i+=1)
             {
@@ -188,7 +188,7 @@ var bf=func(program)
         }
         elsif(c=='<' or c=='>')
         {
-            append(code,mov);
+            append(code,func_table[mov]);
             append(inum,0);
             for(;i<len;i+=1)
             {
@@ -205,17 +205,17 @@ var bf=func(program)
         }
         elsif(c==',')
         {
-            append(code,in);
+            append(code,func_table[in]);
             append(inum,0);
         }
         elsif(c=='.')
         {
-            append(code,out);
+            append(code,func_table[out]);
             append(inum,0);
         }
         elsif(c=='[')
         {
-            append(code,jf);
+            append(code,func_table[jf]);
             append(inum,0);
             append(stack,size(code)-1);
         }
@@ -224,7 +224,7 @@ var bf=func(program)
             if(!size(stack))
                 die("lack [");
             var label=pop(stack);
-            append(code,jt);
+            append(code,func_table[jt]);
             append(inum,label-1);
             inum[label]=size(code)-2;
         }
@@ -233,7 +233,7 @@ var bf=func(program)
         die("lack ]");
     len=size(code);
     for(pc=0;pc<len;pc+=1)
-        func_table[code[pc]]();
+        code[pc]();
     return;
 }
 
diff --git a/test/bfconverter.nas b/test/bfconvertor.nas
similarity index 100%
rename from test/bfconverter.nas
rename to test/bfconvertor.nas
diff --git a/test/bfs.nas b/test/bfs.nas
index 450cd275..84ea9064 100644
--- a/test/bfs.nas
+++ b/test/bfs.nas
@@ -20,7 +20,8 @@ var prt=func()
             s~=map[i][j];
         s~='\n';
     }
-    print(s,'\n');
+    s~='----------\n';
+    print(s);
 }
 
 var bfs=func(begin,end)
@@ -54,8 +55,4 @@ var bfs=func(begin,end)
     return;
 }
 
-prt();
-var begin=[input(),input()];
-var end=[input(),input()];
-bfs(begin,end);
-prt();
\ No newline at end of file
+bfs([0,0],[9,9]);
\ No newline at end of file
diff --git a/test/bigloop.nas b/test/bigloop.nas
index a5ea8b38..453598ab 100644
--- a/test/bigloop.nas
+++ b/test/bigloop.nas
@@ -1 +1 @@
-for(var i=0;i<4000000;i+=1);
\ No newline at end of file
+for(var i=0;i<4e6;i+=1);
\ No newline at end of file
diff --git a/test/bp.nas b/test/bp.nas
index f2bbbaef..db65e86d 100644
--- a/test/bp.nas
+++ b/test/bp.nas
@@ -23,12 +23,9 @@ var diffsigmoid=func(x)
     return x*(1-x);
 }
 
-var inum=2;
-var hnum=4;
-var onum=1;
-var lr=0.1;
+var (inum,hnum,onum,lr)=(2,4,1,0.1);
 var training_set=[[0,0],[0,1],[1,0],[1,1]];
-var expect=[[0],[1],[1],[0]];
+var expect=[0,1,1,0];
 
 var hidden=[];
 for(var i=0;i<hnum;i+=1)
@@ -88,19 +85,12 @@ var run=func(vec)
 }
 var get_error=func(x)
 {
-    var error=0;
-    var expect_set=expect[x];
-    for(var i=0;i<onum;i+=1)
-        error+=(expect_set[i]-output[i].out)*(expect_set[i]-output[i].out);
-    error*=0.5;
-    return error;
+    return 0.5*(expect[x]-output[0].out)*(expect[x]-output[0].out);
 }
 var backward=func(x)
 {
     var input=training_set[x];
-    var expect_set=expect[x];
-    for(var i=0;i<onum;i+=1)
-        output[i].diff=(expect_set[i]-output[i].out)*diffsigmoid(output[i].in);
+    output[0].diff=(expect[x]-output[0].out)*diffsigmoid(output[0].in);
     for(var i=0;i<hnum;i+=1)
     {
         hidden[i].diff=0;
diff --git a/test/calc.nas b/test/calc.nas
index 9eae8012..71b3c53f 100644
--- a/test/calc.nas
+++ b/test/calc.nas
@@ -1,18 +1,32 @@
 import("lib.nas");
 var filename=["main.cpp","nasal_ast.h","nasal_builtin.h","nasal_codegen.h","nasal_gc.h","nasal_import.h","nasal_lexer.h","nasal_parse.h","nasal_vm.h","nasal.h"];
 var space=["       ","    ","","","     "," ","  ","  ","     ","        "];
+var enter_cnt=func(s)
+{
+    var (cnt,len,enter)=(0,size(s),'\n'[0]);
+    for(var i=0;i<len;i+=1)
+        cnt+=(s[i]==enter);
+    return cnt;
+}
+var semic_cnt=func(s)
+{
+    var (cnt,len,semi)=(0,size(s),';'[0]);
+    for(var i=0;i<len;i+=1)
+        cnt+=(s[i]==semi);
+    return cnt;
+}
 func(){
-    var (bytes,cnt,semi)=(0,0,0);
+    var (bytes,line,semi)=(0,0,0);
     forindex(var i;filename)
     {
         var s=io.fin(filename[i]);
         bytes+=size(s);
-        var line_cnt=size(split('\n',s));
-        var semi_cnt=size(split(';' ,s))-1;
+        var line_cnt=enter_cnt(s);
+        var semi_cnt=semic_cnt(s);
         println(filename[i],space[i],'| ',line_cnt,' \tline | ',semi_cnt,' \tsemi');
-        cnt +=line_cnt;
+        line+=line_cnt;
         semi+=semi_cnt;
     }
-    println('total:         | ',cnt,' \tline | ',semi,' \tsemi');
+    println('total:         | ',line,' \tline | ',semi,' \tsemi');
     println('bytes:         | ',bytes,' bytes| ',int(bytes/1024),' \tkb');
 }();
\ No newline at end of file
diff --git a/test/leetcode1319.nas b/test/leetcode1319.nas
index b34890f6..d89c63bb 100644
--- a/test/leetcode1319.nas
+++ b/test/leetcode1319.nas
@@ -1,5 +1,5 @@
 import("lib.nas");
-# 并查集
+# union set
 var n=4;
 var input=[[0,1],[0,2],[1,2]];
 
@@ -23,8 +23,8 @@ var makeConnect=func(n,connections)
     var cnt=n-1;
     var parent=[];
     setsize(parent,n);
-    for(var i=0;i<size(connections);i+=1)
-        if(union_root(connections[i][0],connections[i][1],parent))
+    foreach(var i;connections)
+        if(union_root(i[0],i[1],parent))
             cnt-=1;
     return cnt;
 }
diff --git a/test/lexer.nas b/test/lexer.nas
index a82220e7..eb3872ae 100644
--- a/test/lexer.nas
+++ b/test/lexer.nas
@@ -1,62 +1,8 @@
 import("lib.nas");
 
-var tok_type=
+var lexer=func(file)
 {
-    tok_null:0,
-    tok_num:1,
-    tok_str:2,
-    tok_id:3,
-    tok_for:4,
-    tok_forindex:5,
-    tok_foreach:6,
-    tok_while:7,
-    tok_var:8,
-    tok_func:9,
-    tok_break:10,
-    tok_continue:11,
-    tok_ret:12,
-    tok_if:13,
-    tok_elsif:14,
-    tok_else:15,
-    tok_nil:16,
-    tok_lcurve:17,
-    tok_rcurve:18,
-    tok_lbracket:19,
-    tok_rbracket:20,
-    tok_lbrace:21,
-    tok_rbrace:22,
-    tok_semi:23,
-    tok_and:24,
-    tok_or:25,
-    tok_comma:26,
-    tok_dot:27,
-    tok_ellipsis:28,
-    tok_quesmark:29,
-    tok_colon:30,
-    tok_add:31,
-    tok_sub:32,
-    tok_mult:33,
-    tok_div:34,
-    tok_link:35,
-    tok_not:36,
-    tok_eq:37,
-    tok_addeq:38,
-    tok_subeq:39,
-    tok_multeq:40,
-    tok_diveq:41,
-    tok_lnkeq:42,
-    tok_cmpeq:43,
-    tok_neq:44,
-    tok_less:45,
-    tok_leq:46,
-    tok_grt:47,
-    tok_geq:48,
-	tok_eof:49
-};
-
-var lexer=func(filename)
-{
-    var _={s:io.fin(filename),len:0,ptr:0,token:[]};
+    var _={s:io.fin(file),len:0,ptr:0,token:[]};
     _.len=size(_.s);
     return
     {
@@ -66,23 +12,24 @@ var lexer=func(filename)
                 _.ptr+=1;
             _.ptr+=1;
         },
-        idgen:func()
+        id_gen:func()
         {
             var tmp="";
             while(_.ptr<_.len)
             {
-                if('a'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='z'
-                or 'A'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='Z'
-                or '0'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='9'
-                or chr(_.s[_.ptr])=='_')
-                    tmp~=chr(_.s[_.ptr]);
+                var c=_.s[_.ptr];
+                if(('a'[0]<=c and c<='z'[0])
+                or ('A'[0]<=c and c<='Z'[0])
+                or ('0'[0]<=c and c<='9'[0])
+                or c=='_'[0])
+                    tmp~=chr(c);
                 else
                     break;
                 _.ptr+=1;
             }
             append(_.token,tmp);
         },
-        strgen:func()
+        str_gen:func()
         {
             var str="";
             var mark=chr(_.s[_.ptr]);
@@ -92,19 +39,20 @@ var lexer=func(filename)
                 if(chr(_.s[_.ptr])=='\\')
                 {
                     _.ptr+=1;
-                    if   (chr(_.s[_.ptr])=='a' ) str~='\a';
-                    elsif(chr(_.s[_.ptr])=='b' ) str~='\b';
-                    elsif(chr(_.s[_.ptr])=='f' ) str~='\f';
-                    elsif(chr(_.s[_.ptr])=='n' ) str~='\n';
-                    elsif(chr(_.s[_.ptr])=='r' ) str~='\r';
-                    elsif(chr(_.s[_.ptr])=='t' ) str~='\t';
-                    elsif(chr(_.s[_.ptr])=='v' ) str~='\v';
-                    elsif(chr(_.s[_.ptr])=='?' ) str~='?';
-                    elsif(chr(_.s[_.ptr])=='0' ) str~='\0';
-                    elsif(chr(_.s[_.ptr])=='\\') str~='\\';
-                    elsif(chr(_.s[_.ptr])=='\'') str~='\'';
-                    elsif(chr(_.s[_.ptr])=='\"') str~='\"';
-                    else str~=chr(_.s[_.ptr]);
+                    var c=chr(_.s[_.ptr]);
+                    if   (c=='a' ) str~='\a';
+                    elsif(c=='b' ) str~='\b';
+                    elsif(c=='f' ) str~='\f';
+                    elsif(c=='n' ) str~='\n';
+                    elsif(c=='r' ) str~='\r';
+                    elsif(c=='t' ) str~='\t';
+                    elsif(c=='v' ) str~='\v';
+                    elsif(c=='?' ) str~='?';
+                    elsif(c=='0' ) str~='\0';
+                    elsif(c=='\\') str~='\\';
+                    elsif(c=='\'') str~='\'';
+                    elsif(c=='\"') str~='\"';
+                    else           str~=c;
                 }
                 else
                     str~=chr(_.s[_.ptr]);
@@ -113,88 +61,77 @@ var lexer=func(filename)
             if(_.ptr>=_.len)
                 print("read eof when generating string.\n");
             _.ptr+=1;
-            append(_.token,[tok_type.tok_str,str]);
+            append(_.token,str);
         },
-        numgen:func()
+        num_gen:func()
         {
             var number=chr(_.s[_.ptr]);
             _.ptr+=1;
-            if(chr(_.s[_.ptr])=='x')
+            if(_.ptr<_.len and chr(_.s[_.ptr])=='x')
             {
                 _.ptr+=1;
                 while(_.ptr<_.len and
-                ('a'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='f'
-                or '0'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='9'))
+                ('a'[0]<=_.s[_.ptr] and _.s[_.ptr]<='f'[0]
+                or '0'[0]<=_.s[_.ptr] and _.s[_.ptr]<='9'[0]))
                 {
                     number~=chr(_.s[_.ptr]);
                     _.ptr+=1;
                 }
-                append(_.token,[tok_type.tok_num,num(number)]);
+                append(_.token,num(number));
                 return;
             }
-            elsif(chr(_.s[_.ptr])=='o')
+            elsif(_.ptr<_.len and chr(_.s[_.ptr])=='o')
             {
                 _.ptr+=1;
-                while(_.ptr<_.len and ('0'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='7'))
+                while(_.ptr<_.len and ('0'[0]<=_.s[_.ptr] and _.s[_.ptr]<='7'[0]))
                 {
                     number~=chr(_.s[_.ptr]);
                     _.ptr+=1;
                 }
-                append(_.token,[tok_type.tok_num,num(number)]);
+                append(_.token,num(number));
                 return;
             }
-            while(_.ptr<_.len and ('0'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='9'))
+            while(_.ptr<_.len and ('0'[0]<=_.s[_.ptr] and _.s[_.ptr]<='9'[0]))
             {
                 number~=chr(_.s[_.ptr]);
                 _.ptr+=1;
             }
-            if(chr(_.s[_.ptr])=='.')
-                number~=chr(_.s[_.ptr]);
-            else
-            {
-                append(_.token,[tok_type.tok_num,num(number)]);
-                return;
-            }
-            _.ptr+=1;
-            while(_.ptr<_.len and ('0'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='9'))
+            if(_.ptr<_.len and chr(_.s[_.ptr])=='.')
             {
                 number~=chr(_.s[_.ptr]);
                 _.ptr+=1;
+                while(_.ptr<_.len and ('0'[0]<=_.s[_.ptr] and _.s[_.ptr]<='9'[0]))
+                {
+                    number~=chr(_.s[_.ptr]);
+                    _.ptr+=1;
+                }
             }
             if(chr(_.s[_.ptr])=='e' or chr(_.s[_.ptr])=='E')
-                number~=chr(_.s[_.ptr]);
-            else
-            {
-                append(_.token,[tok_type.tok_num,num(number)]);
-                return;
-            }
-            _.ptr+=1;
-            if(chr(_.s[_.ptr])=='-' or chr(_.s[_.ptr])=='+')
-            {
-                number~=chr(_.s[_.ptr]);
-                _.ptr+=1;
-            }
-            while(_.ptr<_.len and ('0'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='9'))
             {
                 number~=chr(_.s[_.ptr]);
                 _.ptr+=1;
+                if(chr(_.s[_.ptr])=='-' or chr(_.s[_.ptr])=='+')
+                {
+                    number~=chr(_.s[_.ptr]);
+                    _.ptr+=1;
+                }
+                while(_.ptr<_.len and ('0'[0]<=_.s[_.ptr] and _.s[_.ptr]<='9'[0]))
+                {
+                    number~=chr(_.s[_.ptr]);
+                    _.ptr+=1;
+                }
             }
-            append(_.token,[tok_type.tok_num,num(number)]);
+            var last_c=chr(number[-1]);
+            if(last_c=='.' or last_c=='e' or last_c=='E' or last_c=='-' or last_c=='+')
+                println("error number: ",number);
+            append(_.token,num(number));
         },
-        oprgen:func()
+        opr_gen:func()
         {
-            var tmp="";
-            if(chr(_.s[_.ptr])=='+'
-            or chr(_.s[_.ptr])=='-'
-            or chr(_.s[_.ptr])=='~'
-            or chr(_.s[_.ptr])=='/'
-            or chr(_.s[_.ptr])=='*'
-            or chr(_.s[_.ptr])=='>'
-            or chr(_.s[_.ptr])=='<'
-            or chr(_.s[_.ptr])=='!'
-            or chr(_.s[_.ptr])=='=')
+            var c=chr(_.s[_.ptr]);
+            if(c=='+' or c=='-' or c=='~' or c=='/' or c=='*' or c=='>' or c=='<' or c=='!' or c=='=')
             {
-                tmp=chr(_.s[_.ptr]);
+                var tmp=c;
                 _.ptr+=1;
                 if(_.ptr<_.len and chr(_.s[_.ptr])=='=')
                 {
@@ -204,49 +141,42 @@ var lexer=func(filename)
                 append(_.token,tmp);
                 return;
             }
-            elsif(chr(_.s[_.ptr])=='.')
+            elsif(c=='.')
             {
-                if(_.ptr+2<_.len and _.s[_.ptr+1]=='.' and _.s[_.ptr+2]=='.')
+                if(_.ptr+2<_.len and chr(_.s[_.ptr+1])=='.' and chr(_.s[_.ptr+2])=='.')
                 {
-                    tmp='...';
+                    append(_.token,"...");
                     _.ptr+=3;
                 }
                 else
                 {
-                    tmp='.';
+                    append(_.token,".");
                     _.ptr+=1;
                 }
-                append(_.token,tmp);
                 return;
             }
-            elsif(chr(_.s[_.ptr])!=' '
-            and chr(_.s[_.ptr])!='\t'
-            and chr(_.s[_.ptr])!='\n'
-            and chr(_.s[_.ptr])!='\r'
-            and chr(_.s[_.ptr])[0]>0)
-                tmp=chr(_.s[_.ptr]);
+            elsif(c!=' ' and c!='\t' and c!='\n' and c!='\r' and _.s[_.ptr]>0)
+                append(_.token,c);
             _.ptr+=1;
-            if(size(tmp))
-                append(_.token,tmp);
+            return;
         },
         main:func()
         {
             while(_.ptr<_.len)
             {
-                if(chr(_.s[_.ptr])=='#')
+                var c=_.s[_.ptr];
+                if(c=='#'[0])
                     me.jmp_note();
-                elsif('a'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='z'
-                or 'A'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='Z'
-                or chr(_.s[_.ptr])=='_')
-                    me.idgen();
-                elsif(chr(_.s[_.ptr])=='\'' or chr(_.s[_.ptr])=='\"')
-                    me.strgen();
-                elsif('0'<=chr(_.s[_.ptr]) and chr(_.s[_.ptr])<='9')
-                    me.numgen();
+                elsif('a'[0]<=c and c<='z'[0]
+                    or 'A'[0]<=c and c<='Z'[0]
+                    or c=='_'[0])
+                    me.id_gen();
+                elsif(c=='\''[0] or c=='\"'[0])
+                    me.str_gen();
+                elsif('0'[0]<=c and c<='9'[0])
+                    me.num_gen();
                 else
-                    me.oprgen();
-                if(_.ptr>=_.len)
-                    break;
+                    me.opr_gen();
             }
             return;
         },
@@ -254,33 +184,8 @@ var lexer=func(filename)
     };
 }
 
-var parse=func(token)
-{
-    var _={error:0,size:0,token:token,ast:nil};
-    _.size=size(token);
-    return
-    {
-        die:func(info)
-        {
-            _.error+=1;
-            println(info);
-        }
-    };
-}
-
-var ast=func()
-{
-    var _={type:nil,child:[]};
-    return
-    {
-        set_type:func(type){_.type=type;},
-        get_type:func(){return _.type;},
-        add_child:func(child){append(_.child,child);},
-        get_child:func(){return _.child;}
-    };
-}
-
-var nasal_lexer=lexer(input());
+var nasal_lexer=lexer("test/lexer.nas");
 nasal_lexer.main();
-println(nasal_lexer.get_token());
-var nasal_parse=parse(nasal_lexer.get_token());
\ No newline at end of file
+foreach(var tok;nasal_lexer.get_token())
+    print(tok,' ');
+println();
\ No newline at end of file
diff --git a/test/life.nas b/test/life.nas
index fa0f4688..a01740a7 100644
--- a/test/life.nas
+++ b/test/life.nas
@@ -46,8 +46,8 @@ func()
     {
         prt(map);
         var tmp=new_map();
-        forindex(var i;map)
-            forindex(var j;map[i])
+        for(var i=0;i<15;i+=1)
+            for(var j=0;j<20;j+=1)
             {
                 var cnt=0;
                 foreach(var k;calc)
diff --git a/test/quick_sort.nas b/test/quick_sort.nas
index 92c4dd74..97b3affb 100644
--- a/test/quick_sort.nas
+++ b/test/quick_sort.nas
@@ -1,11 +1,8 @@
 import("lib.nas");
-rand(time(0));
 var sort=func(vec,left,right)
 {
-    if(left>=right) return nil;
-    var L=left;
-    var R=right;
-    var tmp=vec[L];
+    if(left>=right) return;
+    var (L,R,tmp)=(left,right,vec[left]);
     while(left<right)
     {
         while(left<right and tmp<=vec[right])
@@ -13,19 +10,15 @@ var sort=func(vec,left,right)
         while(left<right and tmp>=vec[left])
             left+=1;
         if(left!=right)
-        {
-            var t=vec[left];
-            vec[left]=vec[right];
-            vec[right]=t;
-        }
+            (vec[left],vec[right])=(vec[right],vec[left]);
     }
-    vec[L]=vec[left];
-    vec[left]=tmp;
+    (vec[L],vec[left])=(vec[left],tmp);
     sort(vec,L,left-1);
     sort(vec,left+1,R);
-    return nil;
+    return;
 }
 var vec=[];
+rand(time(0));
 for(var i=0;i<200;i+=1)
     append(vec,int(rand()*1000));
 sort(vec,0,size(vec)-1);