diff --git a/nasal.ebnf b/doc/nasal.ebnf
similarity index 100%
rename from nasal.ebnf
rename to doc/nasal.ebnf
diff --git a/main.cpp b/main.cpp
index caf4ef6..732413c 100644
--- a/main.cpp
+++ b/main.cpp
@@ -12,14 +12,14 @@
 #include "nasal_dbg.h"
 #include <unordered_map>
 
-const u32 VM_LEXINFO =0x01;
-const u32 VM_ASTINFO =0x02;
-const u32 VM_CODEINFO=0x04;
-const u32 VM_EXECTIME=0x08;
-const u32 VM_EXEC    =0x10;
-const u32 VM_DETAIL  =0x20;
-const u32 VM_DEBUG   =0x40;
-const u32 VM_OPTIMIZE=0x80;
+const u32 VM_TOKEN =0x01;
+const u32 VM_AST   =0x02;
+const u32 VM_CODE  =0x04;
+const u32 VM_TIME  =0x08;
+const u32 VM_EXEC  =0x10;
+const u32 VM_DETAIL=0x20;
+const u32 VM_DEBUG =0x40;
+const u32 VM_OPT   =0x80;
 
 void help()
 {
@@ -92,7 +92,7 @@ void execute(const string& file,const std::vector<string>& argv,const u32 cmd)
 
     // lexer scans file to get tokens
     lexer.scan(file);
-    if(cmd&VM_LEXINFO)
+    if(cmd&VM_TOKEN)
         lexer.print();
     
     // parser gets lexer's token list to compile
@@ -100,20 +100,20 @@ void execute(const string& file,const std::vector<string>& argv,const u32 cmd)
     // linker gets parser's ast and load import files to this ast
     linker.link(parse,file,cmd&VM_DETAIL);
     // optimizer does simple optimization on ast
-    if(cmd&VM_OPTIMIZE)
+    if(cmd&VM_OPT)
         optimize(parse.ast());
-    if(cmd&VM_ASTINFO)
+    if(cmd&VM_AST)
         parse.print();
     
     // code generator gets parser's ast and linker's import file list to generate code
     gen.compile(parse,linker);
-    if(cmd&VM_CODEINFO)
+    if(cmd&VM_CODE)
         gen.print();
     
     // run
     if(cmd&VM_DEBUG)
         nasal_dbg(nerr).run(gen,linker,argv);
-    else if(cmd&VM_EXECTIME)
+    else if(cmd&VM_TIME)
     {
         auto start=std::chrono::high_resolution_clock::now();
         vm.run(gen,linker,argv,cmd&VM_DETAIL);
@@ -145,13 +145,13 @@ i32 main(i32 argc,const char* argv[])
         return 0;
     }
     std::unordered_map<string,u32> cmdlst={
-        {"--lex",VM_LEXINFO},{"-l",VM_LEXINFO},
-        {"--ast",VM_ASTINFO},{"-a",VM_ASTINFO},
-        {"--code",VM_CODEINFO},{"-c",VM_CODEINFO},
+        {"--lex",VM_TOKEN},{"-l",VM_TOKEN},
+        {"--ast",VM_AST},{"-a",VM_AST},
+        {"--code",VM_CODE},{"-c",VM_CODE},
         {"--exec",VM_EXEC},{"-e",VM_EXEC},
-        {"--time",VM_EXECTIME|VM_EXEC},{"-t",VM_EXECTIME|VM_EXEC},
+        {"--time",VM_TIME|VM_EXEC},{"-t",VM_TIME|VM_EXEC},
         {"--detail",VM_DETAIL|VM_EXEC},{"-d",VM_DETAIL|VM_EXEC},
-        {"--optimize",VM_OPTIMIZE},{"-o",VM_OPTIMIZE},
+        {"--optimize",VM_OPT},{"-o",VM_OPT},
         {"--debug",VM_DEBUG},{"-dbg",VM_DEBUG}
     };
     u32 cmd=0;
diff --git a/makefile b/makefile
index 688ede4..e246b5b 100644
--- a/makefile
+++ b/makefile
@@ -15,58 +15,58 @@ SRC=\
 	nasal_dbg.h\
 	nasal.h
 
-CPPSTANDARD=-std=c++11
+STD=-std=c++11
 
 nasal:$(SRC)
-	$(CXX) $(CPPSTANDARD) -O3 main.cpp -o nasal -fno-exceptions -ldl -Wshadow -Wall
+	$(CXX) $(STD) -O3 main.cpp -o nasal -fno-exceptions -ldl -Wshadow -Wall
 nasal.exe:$(SRC)
-	$(CXX) $(CPPSTANDARD) -O3 main.cpp -o nasal.exe -fno-exceptions -Wshadow -Wall -static
+	$(CXX) $(STD) -O3 main.cpp -o nasal.exe -fno-exceptions -Wshadow -Wall -static
 
 stable-release:$(SRC)
-	$(CXX) $(CPPSTANDARD) -O2 main.cpp -o nasal -fno-exceptions -ldl -Wshadow -Wall
+	$(CXX) $(STD) -O2 main.cpp -o nasal -fno-exceptions -ldl -Wshadow -Wall
 stable-release-mingw:$(SRC)
-	$(CXX) $(CPPSTANDARD) -O2 main.cpp -o nasal.exe -fno-exceptions -Wshadow -Wall -static
+	$(CXX) $(STD) -O2 main.cpp -o nasal.exe -fno-exceptions -Wshadow -Wall -static
 
 test:nasal
-	@ ./nasal -op -e test/ascii-art.nas
-	@ ./nasal -op -c test/auto_crash.nas
-	@ ./nasal -op -a -c test/bf.nas
-	@ ./nasal -op -a -c test/bfcolored.nas
-	@ ./nasal -op -a -c test/bfconvertor.nas
-	@ ./nasal -op -e -d test/bfs.nas
-	@ ./nasal -op -t test/bigloop.nas
-	@ ./nasal -op -e test/bp.nas
-	@ ./nasal -op -e -d test/calc.nas
-	@ ./nasal -op -e test/choice.nas
-	@ ./nasal -op -e test/class.nas
-	@ ./nasal -op -d test/coroutine.nas
-	@ ./nasal -op -e test/diff.nas
-	-@ ./nasal -op -d test/exception.nas
-	@ ./nasal -op -t -d test/fib.nas
-	@ ./nasal -op -e test/filesystem.nas
-	@ ./nasal -op -e -d test/hexdump.nas
-	@ ./nasal -op -c test/httptest.nas
-	@ ./nasal -op -e test/json.nas
-	@ ./nasal -op -e test/leetcode1319.nas
-	@ ./nasal -op -e -d test/lexer.nas
-	@ ./nasal -op -e -d test/life.nas
-	@ ./nasal -op -t test/loop.nas
-	@ ./nasal -op -t -d test/mandel.nas
-	@ ./nasal -op -t -d test/mandelbrot.nas
-	@ ./nasal -op -t -d test/md5.nas
-	@ ./nasal -op -t -d test/md5compare.nas
-	-@ ./nasal -op -d test/module_test.nas
-	@ ./nasal -op -e test/nasal_test.nas
-	@ ./nasal -op -c test/occupation.nas
-	@ ./nasal -op -t -d test/pi.nas
-	@ ./nasal -op -c test/ppmgen.nas
-	@ ./nasal -op -t -d test/prime.nas
-	@ ./nasal -op -e test/qrcode.nas
-	@ ./nasal -op -t -d test/quick_sort.nas
-	@ ./nasal -op -e test/scalar.nas hello world
-	-@ ./nasal -op -c -t test/snake.nas
-	@ ./nasal -op -c -e test/trait.nas
-	-@ ./nasal -op -c -t test/tetris.nas
-	@ ./nasal -op -c -t -d test/turingmachine.nas
-	@ ./nasal -op -c -t -d test/ycombinator.nas
-	@ ./nasal -op -d test/wavecollapse.nas
\ No newline at end of file
+	@ ./nasal -o -e test/ascii-art.nas
+	@ ./nasal -o -c test/auto_crash.nas
+	@ ./nasal -o -a -c test/bf.nas
+	@ ./nasal -o -a -c test/bfcolored.nas
+	@ ./nasal -o -a -c test/bfconvertor.nas
+	@ ./nasal -o -e -d test/bfs.nas
+	@ ./nasal -o -t test/bigloop.nas
+	@ ./nasal -o -e test/bp.nas
+	@ ./nasal -o -e -d test/calc.nas
+	@ ./nasal -o -e test/choice.nas
+	@ ./nasal -o -e test/class.nas
+	@ ./nasal -o -d test/coroutine.nas
+	@ ./nasal -o -e test/diff.nas
+	-@ ./nasal -o -d test/exception.nas
+	@ ./nasal -o -t -d test/fib.nas
+	@ ./nasal -o -e test/filesystem.nas
+	@ ./nasal -o -e -d test/hexdump.nas
+	@ ./nasal -o -c test/httptest.nas
+	@ ./nasal -o -e test/json.nas
+	@ ./nasal -o -e test/leetcode1319.nas
+	@ ./nasal -o -e -d test/lexer.nas
+	@ ./nasal -o -e -d test/life.nas
+	@ ./nasal -o -t test/loop.nas
+	@ ./nasal -o -t -d test/mandel.nas
+	@ ./nasal -o -t -d test/mandelbrot.nas
+	@ ./nasal -o -t -d test/md5.nas
+	@ ./nasal -o -t -d test/md5compare.nas
+	-@ ./nasal -o -d test/module_test.nas
+	@ ./nasal -o -e test/nasal_test.nas
+	@ ./nasal -o -c test/occupation.nas
+	@ ./nasal -o -t -d test/pi.nas
+	@ ./nasal -o -c test/ppmgen.nas
+	@ ./nasal -o -t -d test/prime.nas
+	@ ./nasal -o -e test/qrcode.nas
+	@ ./nasal -o -t -d test/quick_sort.nas
+	@ ./nasal -o -e test/scalar.nas hello world
+	-@ ./nasal -o -c -t test/snake.nas
+	@ ./nasal -o -c -e test/trait.nas
+	-@ ./nasal -o -c -t test/tetris.nas
+	@ ./nasal -o -c -t -d test/turingmachine.nas
+	@ ./nasal -o -c -t -d test/ycombinator.nas
+	@ ./nasal -o -d test/wavecollapse.nas
\ No newline at end of file
diff --git a/nasal_vm.h b/nasal_vm.h
index b108a3b..b378d59 100644
--- a/nasal_vm.h
+++ b/nasal_vm.h
@@ -138,8 +138,8 @@ public:
 
 void nasal_vm::init(
     const std::vector<string>& strs,
-    const std::vector<f64>&         nums,
-    const std::vector<opcode>&      code,
+    const std::vector<f64>&    nums,
+    const std::vector<opcode>& code,
     const std::vector<string>& filenames,
     const std::vector<string>& argv)
 {