diff --git a/doc/nasal.ebnf b/doc/nasal.ebnf
index 604a150..339039c 100644
--- a/doc/nasal.ebnf
+++ b/doc/nasal.ebnf
@@ -10,6 +10,7 @@ nil   ::= nil;
 id    ::= identifier;
 number::= number;
 string::= string;
+bool  ::= true | false;
 vector::= 
     '[' {calculation ','} ']'
 ;
@@ -68,6 +69,7 @@ scalar::=
     |number
     |string
     |nil
+    |bool
     |'(' calculation ')' {call_scalar}
 ;
 call_scalar::=
diff --git a/nasal.h b/nasal.h
index dd8bb7e..c38dcc7 100644
--- a/nasal.h
+++ b/nasal.h
@@ -11,6 +11,30 @@
 #include <cmath>
 #include <vector>
 
+bool is_windows() {
+#if defined _WIN32 || defined _WIN64
+    return true;
+#else
+    return false;
+#endif
+}
+
+bool is_linux() {
+#if defined __linux__
+    return true;
+#else
+    return false;
+#endif
+}
+
+bool is_macos() {
+#if defined __APPLE__
+    return true;
+#else
+    return false;
+#endif
+}
+
 using i32=std::int32_t;
 using i64=std::int64_t;
 using u8=std::uint8_t;
@@ -139,13 +163,11 @@ string chrhex(const char c) {
 string rawstr(const string& str,const usize maxlen=0) {
     string ret("");
     for(auto i:str) {
-#ifdef _WIN32
         // windows doesn't output unicode normally, so we output the hex
-        if (i<=0) {
+        if (is_windows() && i<=0) {
             ret+="\\x"+chrhex(i);
             continue;
         }
-#endif
         switch(i) {
             case '\0':  ret+="\\0"; break;
             case '\a':  ret+="\\a"; break;
diff --git a/nasal_ast.h b/nasal_ast.h
index 0e4e35a..69f00f4 100644
--- a/nasal_ast.h
+++ b/nasal_ast.h
@@ -14,6 +14,7 @@ enum ast_node:u32 {
     ast_num,         // number, basic value type
     ast_str,         // string, basic value type
     ast_id,          // identifier
+    ast_bool,        // bools
     ast_func,        // func keyword
     ast_hash,        // hash, basic value type
     ast_vec,         // vector, basic value type
@@ -71,10 +72,11 @@ const char* ast_name[]={
     "AbstractSyntaxTreeRoot",
     "CodeBlock",
     "FileIndex",
-    "LiteralNil",
-    "LiteralNumber",
-    "LiteralString",
+    "NilLiteral",
+    "NumberLiteral",
+    "StringLiteral",
     "Identifier",
+    "BoolLiteral",
     "Function",
     "HashMap",
     "Vector",
@@ -188,6 +190,7 @@ void ast::print(u32 depth,bool last,std::vector<string>& indent) const{
     std::cout<<ast_name[nd_type];
     if (nd_type==ast_str ||
         nd_type==ast_id ||
+        nd_type==ast_bool ||
         nd_type==ast_default ||
         nd_type==ast_dynamic ||
         nd_type==ast_callh) {
@@ -199,18 +202,14 @@ void ast::print(u32 depth,bool last,std::vector<string>& indent) const{
     if (last && depth) {
         indent.back()="  ";
     } else if (!last && depth) {
-#ifdef _WIN32
-        indent.back()="| ";
-#else
-        indent.back()="│ ";
-#endif
+        indent.back()=is_windows()? "| ":"│ ";
     }
     for(u32 i=0;i<nd_child.size();++i) {
-#ifdef _WIN32
-        indent.push_back(i==nd_child.size()-1?"+-":"|-");
-#else
-        indent.push_back(i==nd_child.size()-1?"└─":"├─");
-#endif
+        if (is_windows()) {
+            indent.push_back(i==nd_child.size()-1?"+-":"|-");
+        } else {
+            indent.push_back(i==nd_child.size()-1?"└─":"├─");
+        }
         nd_child[i].print(depth+1,i==nd_child.size()-1,indent);
         indent.pop_back();
     }
diff --git a/nasal_builtin.h b/nasal_builtin.h
index 9b10bf5..d1e3de7 100644
--- a/nasal_builtin.h
+++ b/nasal_builtin.h
@@ -1005,13 +1005,13 @@ var builtin_dlcall(var* local,gc& ngc) {
 }
 
 var builtin_platform(var* local,gc& ngc) {
-#if defined _WIN32 || defined _WIN64
-    return ngc.newstr("windows");
-#elif defined __linux__
-    return ngc.newstr("linux");
-#elif defined __APPLE__
-    return ngc.newstr("macOS");
-#endif
+    if (is_windows()) {
+        return ngc.newstr("windows");
+    } else if (is_linux()) {
+        return ngc.newstr("linux");
+    } else if (is_macos()) {
+        return ngc.newstr("macOS");
+    }
     return ngc.newstr("unknown");
 }
 
diff --git a/nasal_codegen.h b/nasal_codegen.h
index 511be84..b6cc46a 100644
--- a/nasal_codegen.h
+++ b/nasal_codegen.h
@@ -230,6 +230,7 @@ private:
     void gen(u8,u32,u32);
     void num_gen(const ast&);
     void str_gen(const ast&);
+    void bool_gen(const ast&);
     void vec_gen(const ast&);
     void hash_gen(const ast&);
     void func_gen(const ast&);
@@ -390,6 +391,12 @@ void codegen::str_gen(const ast& node) {
     gen(op_pstr,str_table[node.str()],node.line());
 }
 
+void codegen::bool_gen(const ast& node) {
+    f64 num=node.str()=="true"?1:0;
+    regist_num(num);
+    gen(op_pnum,num_table[num],node.line());
+}
+
 void codegen::vec_gen(const ast& node) {
     for(auto& child:node.child()) {
         calc_gen(child);
@@ -804,7 +811,7 @@ void codegen::for_gen(const ast& node) {
                 gen(op_pop,0,node[0].line());
             }
             break;
-        case ast_nil:case ast_num:case ast_str:break;
+        case ast_nil:case ast_num:case ast_str:case ast_bool:break;
         case ast_vec:case ast_hash:case ast_func:
         case ast_call:
         case ast_neg:case ast_not:
@@ -870,7 +877,7 @@ void codegen::for_gen(const ast& node) {
                 gen(op_pop,0,node[2].line());
             }
             break;
-        case ast_nil:case ast_num:case ast_str:break;
+        case ast_nil:case ast_num:case ast_str:case ast_bool:break;
         case ast_vec:case ast_hash:case ast_func:
         case ast_call:
         case ast_neg:case ast_not:
@@ -1029,6 +1036,7 @@ void codegen::calc_gen(const ast& node) {
         case ast_num:  num_gen(node);  break;
         case ast_str:  str_gen(node);  break;
         case ast_id:   call_id(node);  break;
+        case ast_bool: bool_gen(node); break;
         case ast_vec:  vec_gen(node);  break;
         case ast_hash: hash_gen(node); break;
         case ast_func: func_gen(node); break;
@@ -1122,7 +1130,11 @@ void codegen::calc_gen(const ast& node) {
 void codegen::block_gen(const ast& node) {
     for(auto& tmp:node.child()) {
         switch(tmp.type()) {
-            case ast_null:case ast_nil:case ast_num:case ast_str:break;
+            case ast_null:
+            case ast_nil:
+            case ast_num:
+            case ast_str:
+            case ast_bool:break;
             case ast_file:fileindex=tmp.num();break; // special node type in main block
             case ast_def:def_gen(tmp);break;
             case ast_multi_assign:multi_assign_gen(tmp);break;
diff --git a/nasal_dbg.h b/nasal_dbg.h
index 688b17c..242a69b 100644
--- a/nasal_dbg.h
+++ b/nasal_dbg.h
@@ -145,7 +145,7 @@ void debugger::interact() {
     next=false;
     string cmd;
     stepinfo();
-    while(1) {
+    while(true) {
         std::cout<<">> ";
         std::getline(std::cin,cmd);
         auto res=parse(cmd);
diff --git a/nasal_import.h b/nasal_import.h
index 1bc9f7d..d296d58 100644
--- a/nasal_import.h
+++ b/nasal_import.h
@@ -39,11 +39,7 @@ public:
 };
 
 linker::linker(error& e):show_path(false),lib_loaded(false),err(e) {
-#ifdef _WIN32
-    char sep=';';
-#else
-    char sep=':';
-#endif
+    char sep=is_windows()? ';':':';
     string PATH=getenv("PATH");
     usize last=0,pos=PATH.find(sep,0);
     while(pos!=string::npos) {
@@ -77,11 +73,7 @@ string linker::path(const ast& node) {
 string linker::findf(const string& fname) {
     std::vector<string> fpath={fname};
     for(auto&p:envpath) {
-#ifdef _WIN32
-        fpath.push_back(p+"\\"+fname);
-#else
-        fpath.push_back(p+"/"+fname);
-#endif
+        fpath.push_back(p+(is_windows()? "\\":"/")+fname);
     }
     for(auto& i:fpath) {
         if (access(i.c_str(),F_OK)!=-1) {
@@ -89,11 +81,7 @@ string linker::findf(const string& fname) {
         }
     }
     if (fname=="lib.nas") {
-#ifdef _WIN32
-        return findf("stl\\lib.nas");
-#else
-        return findf("stl/lib.nas");
-#endif
+        return is_windows()? findf("stl\\lib.nas"):findf("stl/lib.nas");
     }
     if (!show_path) {
         err.err("link","cannot find file <"+fname+">");
diff --git a/nasal_lexer.h b/nasal_lexer.h
index cb9e51d..ddcc3a9 100644
--- a/nasal_lexer.h
+++ b/nasal_lexer.h
@@ -18,6 +18,8 @@ enum class tok:u32 {
     num,      // number literal
     str,      // string literal
     id,       // identifier
+    tktrue,   // keyword true
+    tkfalse,  // keyword false
     rfor,     // loop keyword for
     forindex, // loop keyword forindex
     foreach,  // loop keyword foreach
@@ -88,6 +90,8 @@ private:
     error& err;
     std::vector<token> toks;
     std::unordered_map<string,tok> typetbl {
+        {"true"    ,tok::tktrue  },
+        {"false"   ,tok::tkfalse },
         {"for"     ,tok::rfor    },
         {"forindex",tok::forindex},
         {"foreach" ,tok::foreach },
diff --git a/nasal_parse.h b/nasal_parse.h
index 5f79853..541e989 100644
--- a/nasal_parse.h
+++ b/nasal_parse.h
@@ -116,6 +116,7 @@ private:
     ast num();
     ast str();
     ast id();
+    ast bools();
     ast vec();
     ast hash();
     ast pair();
@@ -337,13 +338,24 @@ ast parse::id() {
     return node;
 }
 
+ast parse::bools() {
+    ast node(toks[ptr].tk_end_line,toks[ptr].tk_end_column,ast_bool,toks[ptr].file);
+    node.set_str(toks[ptr].str);
+    if (lookahead(tok::tktrue)) {
+        match(tok::tktrue);
+    } else {
+        match(tok::tkfalse);
+    }
+    return node;
+}
+
 ast parse::vec() {
     // panic set for this token is not ','
     // this is the FIRST set of calculation
     // array end with tok::null=0
     const tok panic[]={
-        tok::id,tok::str,tok::num,
-        tok::opnot,tok::sub,tok::tknil,
+        tok::id,tok::str,tok::num,tok::tktrue,
+        tok::tkfalse,tok::opnot,tok::sub,tok::tknil,
         tok::func,tok::var,tok::lcurve,
         tok::lbrace,tok::lbracket,tok::null
     };
@@ -460,6 +472,8 @@ ast parse::expr()
         case tok::num:
         case tok::str:
         case tok::id:
+        case tok::tktrue:
+        case tok::tkfalse:
         case tok::func:
         case tok::lbracket:
         case tok::lbrace:
@@ -621,6 +635,8 @@ ast parse::scalar() {
         node=str();
     } else if (lookahead(tok::id)) {
         node=id();
+    } else if (lookahead(tok::tktrue) || lookahead(tok::tkfalse)) {
+        node=bools();
     } else if (lookahead(tok::func)) {
         node=func();
     } else if (lookahead(tok::lbracket)) {
@@ -677,8 +693,8 @@ ast parse::callv() {
     // this is the FIRST set of subvec
     // array end with tok::null=0
     const tok panic[]={
-        tok::id,tok::str,tok::num,
-        tok::opnot,tok::sub,tok::tknil,
+        tok::id,tok::str,tok::num,tok::tktrue,
+        tok::tkfalse,tok::opnot,tok::sub,tok::tknil,
         tok::func,tok::var,tok::lcurve,
         tok::lbrace,tok::lbracket,tok::colon,
         tok::null
@@ -707,8 +723,8 @@ ast parse::callf() {
     // this is the FIRST set of calculation/hashmember
     // array end with tok::null=0
     const tok panic[]={
-        tok::id,tok::str,tok::num,
-        tok::opnot,tok::sub,tok::tknil,
+        tok::id,tok::str,tok::num,tok::tktrue,
+        tok::tkfalse,tok::opnot,tok::sub,tok::tknil,
         tok::func,tok::var,tok::lcurve,
         tok::lbrace,tok::lbracket,tok::null
     };
@@ -798,8 +814,8 @@ ast parse::multi_id() {
 ast parse::multi_scalar() {
     // if check_call_memory is true,we will check if value called here can reach a memory space
     const tok panic[]={
-        tok::id,tok::str,tok::num,
-        tok::opnot,tok::sub,tok::tknil,
+        tok::id,tok::str,tok::num,tok::tktrue,
+        tok::tkfalse,tok::opnot,tok::sub,tok::tknil,
         tok::func,tok::var,tok::lcurve,
         tok::lbrace,tok::lbracket,tok::null
     };
diff --git a/test/nasal_test.nas b/test/nasal_test.nas
index b430a4c..60f40dd 100644
--- a/test/nasal_test.nas
+++ b/test/nasal_test.nas
@@ -51,6 +51,7 @@ z.funcc();                       #//f is called
 println(z.funcccall);            #//func(..){..}
 z2.listt2[3].hashh.funcc();      #//f is called
 println(y1[f2()][w]);            #//hello
+println(true,' ',false);         #//1 0
 
 
 # ValKmjolnir
diff --git a/test/scalar.nas b/test/scalar.nas
index d9350f4..ec6a0d3 100644
--- a/test/scalar.nas
+++ b/test/scalar.nas
@@ -203,5 +203,5 @@ foreach(i;a){
 }
 println(runtime.argv());
 func(a,b,c,d="只有红茶可以吗"){
-    println(a,' ',b,' ',c,' ',d);
+    println(a,' ',b,' ',c,' ',d,' true: ',true,' false: ',false);
 }(c:1919810,b:514,a:114);
\ No newline at end of file