diff --git a/include/pocketpy/compiler/compiler.hpp b/include/pocketpy/compiler/compiler.hpp
index 39132cc2..bdb06812 100644
--- a/include/pocketpy/compiler/compiler.hpp
+++ b/include/pocketpy/compiler/compiler.hpp
@@ -17,7 +17,7 @@ struct PrattRule {
 struct Compiler {
     PK_ALWAYS_PASS_BY_POINTER(Compiler)
 
-    static PrattRule rules[kTokenCount];
+    static PrattRule rules[TK__COUNT__];
 
     Lexer lexer;
     vector<CodeEmitContext> contexts;
@@ -43,7 +43,7 @@ struct Compiler {
             printf("%s:%d %s %s\n",
                 lexer.src.filename().c_str(),
                 curr().line,
-                TK_STR(curr().type),
+                pk_TokenSymbols(curr().type),
                 curr().str().escape().c_str()
             );
         }
diff --git a/include/pocketpy/compiler/lexer.h b/include/pocketpy/compiler/lexer.h
index cd3dc35b..c3b49306 100644
--- a/include/pocketpy/compiler/lexer.h
+++ b/include/pocketpy/compiler/lexer.h
@@ -7,11 +7,38 @@
 extern "C" {
 #endif
 
+extern const char* pk_TokenSymbols[];
+
 typedef struct pkpy_TokenDeserializer {
     const char* curr;
     const char* source;
 } pkpy_TokenDeserializer;
 
+enum TokenIndex{
+    TK_EOF, TK_EOL, TK_SOF,
+    TK_ID, TK_NUM, TK_STR, TK_FSTR, TK_LONG, TK_BYTES, TK_IMAG,
+    TK_INDENT, TK_DEDENT,
+    /***************/
+    TK_IS_NOT, TK_NOT_IN, TK_YIELD_FROM,
+    /***************/
+    TK_ADD, TK_IADD, TK_SUB, TK_ISUB,
+    TK_MUL, TK_IMUL, TK_DIV, TK_IDIV, TK_FLOORDIV, TK_IFLOORDIV, TK_MOD, TK_IMOD,
+    TK_AND, TK_IAND, TK_OR, TK_IOR, TK_XOR, TK_IXOR,
+    TK_LSHIFT, TK_ILSHIFT, TK_RSHIFT, TK_IRSHIFT,
+    /***************/
+    TK_LPAREN, TK_RPAREN, TK_LBRACKET, TK_RBRACKET, TK_LBRACE, TK_RBRACE,
+    TK_DOT, TK_DOTDOT, TK_DOTDOTDOT, TK_COMMA, TK_COLON, TK_SEMICOLON,
+    TK_POW, TK_ARROW, TK_HASH, TK_DECORATOR,
+    TK_GT, TK_LT, TK_ASSIGN, TK_EQ, TK_NE, TK_GE, TK_LE, TK_INVERT,
+    /***************/
+    TK_FALSE, TK_NONE, TK_TRUE, TK_AND_KW, TK_AS, TK_ASSERT, TK_BREAK, TK_CLASS, TK_CONTINUE,
+    TK_DEF, TK_DEL, TK_ELIF, TK_ELSE, TK_EXCEPT, TK_FINALLY, TK_FOR, TK_FROM, TK_GLOBAL,
+    TK_IF, TK_IMPORT, TK_IN, TK_IS, TK_LAMBDA, TK_NOT_KW, TK_OR_KW, TK_PASS, TK_RAISE, TK_RETURN,
+    TK_TRY, TK_WHILE, TK_WITH, TK_YIELD,
+    /***************/
+    TK__COUNT__
+};
+
 void pkpy_TokenDeserializer__ctor(pkpy_TokenDeserializer* self, const char* source);
 bool pkpy_TokenDeserializer__match_char(pkpy_TokenDeserializer* self, char c);
 c11_string pkpy_TokenDeserializer__read_string(pkpy_TokenDeserializer* self, char c);
diff --git a/include/pocketpy/compiler/lexer.hpp b/include/pocketpy/compiler/lexer.hpp
index c2301b18..955bc45c 100644
--- a/include/pocketpy/compiler/lexer.hpp
+++ b/include/pocketpy/compiler/lexer.hpp
@@ -2,58 +2,15 @@
 
 #include "pocketpy/objects/error.hpp"
 #include "pocketpy/objects/sourcedata.h"
+#include "pocketpy/compiler/lexer.h"
 
 #include <variant>
 
 namespace pkpy {
 
-typedef uint8_t TokenIndex;
-
-// clang-format off
-constexpr const char* kTokens[] = {
-    "@eof", "@eol", "@sof",
-    "@id", "@num", "@str", "@fstr", "@long", "@bytes", "@imag",
-    "@indent", "@dedent",
-    // These 3 are compound keywords which are generated on the fly
-    "is not", "not in", "yield from",
-    /*****************************************/
-    "+", "+=", "-", "-=",   // (INPLACE_OP - 1) can get '=' removed
-    "*", "*=", "/", "/=", "//", "//=", "%", "%=",
-    "&", "&=", "|", "|=", "^", "^=", 
-    "<<", "<<=", ">>", ">>=",
-    /*****************************************/
-    "(", ")", "[", "]", "{", "}",
-    ".", "..", "...", ",", ":", ";",
-    "**", "->", "#", "@",
-    ">", "<", "=", "==", "!=", ">=", "<=", "~",
-    /** KW_BEGIN **/
-    // NOTE: These keywords should be sorted in ascending order!!
-    "False", "None", "True", "and", "as", "assert", "break", "class", "continue",
-    "def", "del", "elif", "else", "except", "finally", "for", "from", "global",
-    "if", "import", "in", "is", "lambda", "not", "or", "pass", "raise", "return",
-    "try", "while", "with", "yield",
-};
-// clang-format on
-
 using TokenValue = std::variant<std::monostate, i64, f64, Str>;
-const int kTokenCount = sizeof(kTokens) / sizeof(kTokens[0]);
 
-constexpr TokenIndex TK(const char token[]) {
-    for(int k = 0; k < kTokenCount; k++) {
-        const char* i = kTokens[k];
-        const char* j = token;
-        while(*i && *j && *i == *j) {
-            i++;
-            j++;
-        }
-        if(*i == *j) return k;
-    }
-    return 255;
-}
-
-constexpr inline bool is_raw_string_used(TokenIndex t) noexcept{ return t == TK("@id") || t == TK("@long"); }
-
-#define TK_STR(t) kTokens[t]
+constexpr inline bool is_raw_string_used(TokenIndex t) noexcept{ return t == TK_ID || t == TK_LONG; }
 
 struct Token {
     TokenIndex type;
diff --git a/src/common/str.c b/src/common/str.c
index 7b7705d4..ff6fec7d 100644
--- a/src/common/str.c
+++ b/src/common/str.c
@@ -406,6 +406,7 @@ bool c11__is_unicode_Lo_char(int c){
     if(c == 0x1f955) return true;
     int index;
     c11__lower_bound(const int, kLoRangeA, 476, c, c11__less, &index);
+    if(index == 476) return false;
     if(c == kLoRangeA[index]) return true;
     index -= 1;
     if(index < 0) return false;
diff --git a/src/compiler/compiler.cpp b/src/compiler/compiler.cpp
index 4572d897..56a21fc0 100644
--- a/src/compiler/compiler.cpp
+++ b/src/compiler/compiler.cpp
@@ -6,12 +6,12 @@
 
 namespace pkpy {
 
-#define consume(expected) if(!match(expected)) return SyntaxError("expected '%s', got '%s'", TK_STR(expected), TK_STR(curr().type));
+#define consume(expected) if(!match(expected)) return SyntaxError("expected '%s', got '%s'", pk_TokenSymbols[expected], pk_TokenSymbols[curr().type]);
 #define consume_end_stmt() if(!match_end_stmt()) return SyntaxError("expected statement end")
 #define check_newlines_repl() { bool __nml; match_newlines(&__nml); if(__nml) return NeedMoreLines(); }
 #define check(B) if((err = B)) return err
 
-PrattRule Compiler::rules[kTokenCount];
+PrattRule Compiler::rules[TK__COUNT__];
 
 NameScope Compiler::name_scope() const noexcept{
     auto s = contexts.size() > 1 ? NAME_LOCAL : NAME_GLOBAL;
@@ -44,7 +44,7 @@ Error* Compiler::pop_context() noexcept{
     ctx()->emit_(OP_RETURN_VALUE, 1, BC_KEEPLINE, true);
     // find the last valid token
     int j = __i - 1;
-    while(tk(j).type == TK("@eol") || tk(j).type == TK("@dedent") || tk(j).type == TK("@eof"))
+    while(tk(j).type == TK_EOL || tk(j).type == TK_DEDENT || tk(j).type == TK_EOF)
         j--;
     ctx()->co->end_line = tk(j).line;
 
@@ -115,52 +115,52 @@ void Compiler::init_pratt_rules() noexcept{
 // http://journal.stuffwithstuff.com/2011/03/19/pratt-parsers-expression-parsing-made-easy/
 #define PK_METHOD(name) &Compiler::name
 #define PK_NO_INFIX nullptr, PREC_LOWEST
-        for(TokenIndex i = 0; i < kTokenCount; i++) rules[i] = { nullptr, PK_NO_INFIX };
-        rules[TK(".")] =        { nullptr,                  PK_METHOD(exprAttrib),         PREC_PRIMARY };
-        rules[TK("(")] =        { PK_METHOD(exprGroup),     PK_METHOD(exprCall),           PREC_PRIMARY };
-        rules[TK("[")] =        { PK_METHOD(exprList),      PK_METHOD(exprSubscr),         PREC_PRIMARY };
-        rules[TK("{")] =        { PK_METHOD(exprMap),       PK_NO_INFIX };
-        rules[TK("%")] =        { nullptr,                  PK_METHOD(exprBinaryOp),       PREC_FACTOR };
-        rules[TK("+")] =        { nullptr,                  PK_METHOD(exprBinaryOp),       PREC_TERM };
-        rules[TK("-")] =        { PK_METHOD(exprUnaryOp),   PK_METHOD(exprBinaryOp),       PREC_TERM };
-        rules[TK("*")] =        { PK_METHOD(exprUnaryOp),   PK_METHOD(exprBinaryOp),       PREC_FACTOR };
-        rules[TK("~")] =        { PK_METHOD(exprUnaryOp),   nullptr,                    PREC_UNARY };
-        rules[TK("/")] =        { nullptr,                  PK_METHOD(exprBinaryOp),       PREC_FACTOR };
-        rules[TK("//")] =       { nullptr,                  PK_METHOD(exprBinaryOp),       PREC_FACTOR };
-        rules[TK("**")] =       { PK_METHOD(exprUnaryOp),   PK_METHOD(exprBinaryOp),       PREC_EXPONENT };
-        rules[TK(">")] =        { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("<")] =        { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("==")] =       { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("!=")] =       { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK(">=")] =       { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("<=")] =       { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("in")] =       { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("is")] =       { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("<<")] =       { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_SHIFT };
-        rules[TK(">>")] =       { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_SHIFT };
-        rules[TK("&")] =        { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_AND };
-        rules[TK("|")] =        { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_OR };
-        rules[TK("^")] =        { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_XOR };
-        rules[TK("@")] =        { nullptr,               PK_METHOD(exprBinaryOp),       PREC_FACTOR };
-        rules[TK("if")] =       { nullptr,               PK_METHOD(exprTernary),        PREC_TERNARY };
-        rules[TK("not in")] =   { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("is not")] =   { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
-        rules[TK("and") ] =     { nullptr,               PK_METHOD(exprAnd),            PREC_LOGICAL_AND };
-        rules[TK("or")] =       { nullptr,               PK_METHOD(exprOr),             PREC_LOGICAL_OR };
-        rules[TK("not")] =      { PK_METHOD(exprNot),       nullptr,                    PREC_LOGICAL_NOT };
-        rules[TK("True")] =     { PK_METHOD(exprLiteral0),  PK_NO_INFIX };
-        rules[TK("False")] =    { PK_METHOD(exprLiteral0),  PK_NO_INFIX };
-        rules[TK("None")] =     { PK_METHOD(exprLiteral0),  PK_NO_INFIX };
-        rules[TK("...")] =      { PK_METHOD(exprLiteral0),  PK_NO_INFIX };
-        rules[TK("lambda")] =   { PK_METHOD(exprLambda),    PK_NO_INFIX };
-        rules[TK("@id")] =      { PK_METHOD(exprName),      PK_NO_INFIX };
-        rules[TK("@num")] =     { PK_METHOD(exprLiteral),   PK_NO_INFIX };
-        rules[TK("@str")] =     { PK_METHOD(exprLiteral),   PK_NO_INFIX };
-        rules[TK("@fstr")] =    { PK_METHOD(exprFString),   PK_NO_INFIX };
-        rules[TK("@long")] =    { PK_METHOD(exprLong),      PK_NO_INFIX };
-        rules[TK("@imag")] =    { PK_METHOD(exprImag),      PK_NO_INFIX };
-        rules[TK("@bytes")] =   { PK_METHOD(exprBytes),     PK_NO_INFIX };
-        rules[TK(":")] =        { PK_METHOD(exprSlice0),    PK_METHOD(exprSlice1),      PREC_PRIMARY };
+        for(int i = 0; i < TK__COUNT__; i++) rules[i] = { nullptr, PK_NO_INFIX };
+        rules[TK_DOT] =             { nullptr,                  PK_METHOD(exprAttrib),         PREC_PRIMARY };
+        rules[TK_LPAREN] =          { PK_METHOD(exprGroup),     PK_METHOD(exprCall),           PREC_PRIMARY };
+        rules[TK_LBRACKET] =        { PK_METHOD(exprList),      PK_METHOD(exprSubscr),         PREC_PRIMARY };
+        rules[TK_LBRACE] =          { PK_METHOD(exprMap),       PK_NO_INFIX };
+        rules[TK_MOD] =             { nullptr,                  PK_METHOD(exprBinaryOp),       PREC_FACTOR };
+        rules[TK_ADD] =             { nullptr,                  PK_METHOD(exprBinaryOp),       PREC_TERM };
+        rules[TK_SUB] =             { PK_METHOD(exprUnaryOp),   PK_METHOD(exprBinaryOp),       PREC_TERM };
+        rules[TK_MUL] =             { PK_METHOD(exprUnaryOp),   PK_METHOD(exprBinaryOp),       PREC_FACTOR };
+        rules[TK_INVERT] =          { PK_METHOD(exprUnaryOp),   nullptr,                        PREC_UNARY };
+        rules[TK_DIV] =             { nullptr,                  PK_METHOD(exprBinaryOp),        PREC_FACTOR };
+        rules[TK_FLOORDIV] =        { nullptr,                  PK_METHOD(exprBinaryOp),        PREC_FACTOR };
+        rules[TK_POW] =         { PK_METHOD(exprUnaryOp),   PK_METHOD(exprBinaryOp),       PREC_EXPONENT };
+        rules[TK_GT] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_LT] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_EQ] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_NE] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_GE] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_LE] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_IN] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_IS] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_LSHIFT] =      { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_SHIFT };
+        rules[TK_RSHIFT] =      { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_SHIFT };
+        rules[TK_AND] =         { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_AND };
+        rules[TK_OR] =          { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_OR };
+        rules[TK_XOR] =         { nullptr,               PK_METHOD(exprBinaryOp),       PREC_BITWISE_XOR };
+        rules[TK_DECORATOR] =   { nullptr,               PK_METHOD(exprBinaryOp),       PREC_FACTOR };
+        rules[TK_IF] =          { nullptr,               PK_METHOD(exprTernary),        PREC_TERNARY };
+        rules[TK_NOT_IN] =      { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_IS_NOT] =      { nullptr,               PK_METHOD(exprBinaryOp),       PREC_COMPARISION };
+        rules[TK_AND_KW ] =     { nullptr,               PK_METHOD(exprAnd),            PREC_LOGICAL_AND };
+        rules[TK_OR_KW] =       { nullptr,               PK_METHOD(exprOr),             PREC_LOGICAL_OR };
+        rules[TK_NOT_KW] =      { PK_METHOD(exprNot),       nullptr,                    PREC_LOGICAL_NOT };
+        rules[TK_TRUE] =        { PK_METHOD(exprLiteral0),  PK_NO_INFIX };
+        rules[TK_FALSE] =       { PK_METHOD(exprLiteral0),  PK_NO_INFIX };
+        rules[TK_NONE] =        { PK_METHOD(exprLiteral0),  PK_NO_INFIX };
+        rules[TK_DOTDOTDOT] =   { PK_METHOD(exprLiteral0),  PK_NO_INFIX };
+        rules[TK_LAMBDA] =      { PK_METHOD(exprLambda),    PK_NO_INFIX };
+        rules[TK_ID] =          { PK_METHOD(exprName),      PK_NO_INFIX };
+        rules[TK_NUM] =         { PK_METHOD(exprLiteral),   PK_NO_INFIX };
+        rules[TK_STR] =         { PK_METHOD(exprLiteral),   PK_NO_INFIX };
+        rules[TK_FSTR] =        { PK_METHOD(exprFString),   PK_NO_INFIX };
+        rules[TK_LONG] =        { PK_METHOD(exprLong),      PK_NO_INFIX };
+        rules[TK_IMAG] =        { PK_METHOD(exprImag),      PK_NO_INFIX };
+        rules[TK_BYTES] =       { PK_METHOD(exprBytes),     PK_NO_INFIX };
+        rules[TK_COLON] =       { PK_METHOD(exprSlice0),    PK_METHOD(exprSlice1),      PREC_PRIMARY };
         
 #undef PK_METHOD
 #undef PK_NO_INFIX
@@ -175,30 +175,30 @@ bool Compiler::match(TokenIndex expected) noexcept{
 
 bool Compiler::match_newlines(bool* need_more_lines) noexcept{
     bool consumed = false;
-    if(curr().type == TK("@eol")) {
-        while(curr().type == TK("@eol")) advance();
+    if(curr().type == TK_EOL) {
+        while(curr().type == TK_EOL) advance();
         consumed = true;
     }
     if(need_more_lines) {
-        *need_more_lines = (mode() == REPL_MODE && curr().type == TK("@eof"));
+        *need_more_lines = (mode() == REPL_MODE && curr().type == TK_EOF);
     }
     return consumed;
 }
 
 bool Compiler::match_end_stmt() noexcept{
-    if(match(TK(";"))) {
+    if(match(TK_SEMICOLON)) {
         match_newlines();
         return true;
     }
-    if(match_newlines() || curr().type == TK("@eof")) return true;
-    if(curr().type == TK("@dedent")) return true;
+    if(match_newlines() || curr().type == TK_EOF) return true;
+    if(curr().type == TK_DEDENT) return true;
     return false;
 }
 
 Error* Compiler::EXPR_TUPLE(bool allow_slice) noexcept{
     Error* err;
     check(parse_expression(PREC_LOWEST + 1, allow_slice));
-    if(!match(TK(","))) return NULL;
+    if(!match(TK_COMMA)) return NULL;
     // tuple expression
     int count = 1;
     do {
@@ -207,7 +207,7 @@ Error* Compiler::EXPR_TUPLE(bool allow_slice) noexcept{
         check(parse_expression(PREC_LOWEST + 1, allow_slice));
         count += 1;
         if(curr().brackets_level) check_newlines_repl();
-    } while(match(TK(",")));
+    } while(match(TK_COMMA));
     TupleExpr* e = make_expr<TupleExpr>(count);
     for(int i=count-1; i>=0; i--)
         e->items[i] = ctx()->s_popx();
@@ -218,10 +218,10 @@ Error* Compiler::EXPR_TUPLE(bool allow_slice) noexcept{
 Error* Compiler::EXPR_VARS() noexcept{
     int count = 0;
     do {
-        consume(TK("@id"));
+        consume(TK_ID);
         ctx()->s_push(make_expr<NameExpr>(prev().str(), name_scope()));
         count += 1;
-    } while(match(TK(",")));
+    } while(match(TK_COMMA));
     if(count > 1){
         TupleExpr* e = make_expr<TupleExpr>(count);
         for(int i=count-1; i>=0; i--)
@@ -260,9 +260,9 @@ Error* Compiler::exprLambda() noexcept{
     Error* err;
     FuncDecl_ decl = push_f_context("<lambda>");
     int line = prev().line;     // backup line
-    if(!match(TK(":"))) {
+    if(!match(TK_COLON)) {
         check(_compile_f_args(decl, false));
-        consume(TK(":"));
+        consume(TK_COLON);
     }
     // https://github.com/pocketpy/pocketpy/issues/37
     check(parse_expression(PREC_LAMBDA + 1));
@@ -304,7 +304,7 @@ Error* Compiler::exprTernary() noexcept{
     Error* err;
     int line = prev().line;
     check(parse_expression(PREC_TERNARY + 1));  // [true_expr, cond]
-    consume(TK("else"));
+    consume(TK_ELSE);
     check(parse_expression(PREC_TERNARY + 1));  // [true_expr, cond, false_expr]
     auto e = make_expr<TernaryExpr>();
     e->line = line;
@@ -341,10 +341,10 @@ Error* Compiler::exprUnaryOp() noexcept{
     TokenIndex op = prev().type;
     check(parse_expression(PREC_UNARY + 1));
     switch(op) {
-        case TK("-"): ctx()->s_push(make_expr<NegatedExpr>(ctx()->s_popx())); break;
-        case TK("~"): ctx()->s_push(make_expr<InvertExpr>(ctx()->s_popx())); break;
-        case TK("*"): ctx()->s_push(make_expr<StarredExpr>(ctx()->s_popx(), 1)); break;
-        case TK("**"): ctx()->s_push(make_expr<StarredExpr>(ctx()->s_popx(), 2)); break;
+        case TK_SUB: ctx()->s_push(make_expr<NegatedExpr>(ctx()->s_popx())); break;
+        case TK_INVERT: ctx()->s_push(make_expr<InvertExpr>(ctx()->s_popx())); break;
+        case TK_MUL: ctx()->s_push(make_expr<StarredExpr>(ctx()->s_popx(), 1)); break;
+        case TK_POW: ctx()->s_push(make_expr<StarredExpr>(ctx()->s_popx(), 2)); break;
         default: assert(false);
     }
     return NULL;
@@ -355,7 +355,7 @@ Error* Compiler::exprGroup() noexcept{
     check_newlines_repl()
     check(EXPR_TUPLE());  // () is just for change precedence
     check_newlines_repl()
-    consume(TK(")"));
+    consume(TK_RPAREN);
     if(ctx()->s_top()->is_tuple()) return NULL;
     Expr* g = make_expr<GroupedExpr>(ctx()->s_popx());
     ctx()->s_push(g);
@@ -367,10 +367,10 @@ Error* Compiler::consume_comp(Opcode op0, Opcode op1) noexcept{
     Error* err;
     bool has_cond = false;
     check(EXPR_VARS());                         // [expr, vars]
-    consume(TK("in"));
+    consume(TK_IN);
     check(parse_expression(PREC_TERNARY + 1));  // [expr, vars, iter]
     check_newlines_repl()
-    if(match(TK("if"))) {
+    if(match(TK_IF)) {
         check(parse_expression(PREC_TERNARY + 1));  // [expr, vars, iter, cond]
         has_cond = true;
     }
@@ -390,17 +390,17 @@ Error* Compiler::exprList() noexcept{
     int count = 0;
     do {
         check_newlines_repl()
-        if(curr().type == TK("]")) break;
+        if(curr().type == TK_RBRACKET) break;
         check(EXPR()); count += 1;
         check_newlines_repl()
-        if(count == 1 && match(TK("for"))) {
+        if(count == 1 && match(TK_FOR)) {
             check(consume_comp(OP_BUILD_LIST, OP_LIST_APPEND));
-            consume(TK("]"));
+            consume(TK_RBRACKET);
             return NULL;
         }
         check_newlines_repl()
-    } while(match(TK(",")));
-    consume(TK("]"));
+    } while(match(TK_COMMA));
+    consume(TK_RBRACKET);
     ListExpr* e = make_expr<ListExpr>(count);
     e->line = line;  // override line
     for(int i=count-1; i>=0; i--)
@@ -415,10 +415,10 @@ Error* Compiler::exprMap() noexcept{
     int count = 0;
     do {
         check_newlines_repl()
-        if(curr().type == TK("}")) break;
+        if(curr().type == TK_RBRACE) break;
         check(EXPR());  // [key]
         int star_level = ctx()->s_top()->star_level();
-        if(star_level == 2 || curr().type == TK(":")) { parsing_dict = true; }
+        if(star_level == 2 || curr().type == TK_COLON) { parsing_dict = true; }
         if(parsing_dict) {
             if(star_level == 2) {
                 DictItemExpr* dict_item = make_expr<DictItemExpr>();
@@ -426,7 +426,7 @@ Error* Compiler::exprMap() noexcept{
                 dict_item->value = ctx()->s_popx();
                 ctx()->s_push(dict_item);
             } else {
-                consume(TK(":"));
+                consume(TK_COLON);
                 check(EXPR());
                 DictItemExpr* dict_item = make_expr<DictItemExpr>();
                 dict_item->value = ctx()->s_popx();
@@ -436,18 +436,18 @@ Error* Compiler::exprMap() noexcept{
         }
         count += 1;
         check_newlines_repl()
-        if(count == 1 && match(TK("for"))) {
+        if(count == 1 && match(TK_FOR)) {
             if(parsing_dict){
                 check(consume_comp(OP_BUILD_DICT, OP_DICT_ADD));
             }else{
                 check(consume_comp(OP_BUILD_SET, OP_SET_ADD));
             }
-            consume(TK("}"));
+            consume(TK_RBRACE);
             return NULL;
         }
         check_newlines_repl()
-    } while(match(TK(",")));
-    consume(TK("}"));
+    } while(match(TK_COMMA));
+    consume(TK_RBRACE);
 
     SequenceExpr* se;
     if(count == 0 || parsing_dict) {
@@ -468,11 +468,11 @@ Error* Compiler::exprCall() noexcept{
     ctx()->s_push(e);     // push onto the stack in advance
     do {
         check_newlines_repl()
-        if(curr().type == TK(")")) break;
-        if(curr().type == TK("@id") && next().type == TK("=")) {
-            consume(TK("@id"));
+        if(curr().type == TK_RPAREN) break;
+        if(curr().type == TK_ID && next().type == TK_ASSIGN) {
+            consume(TK_ID);
             StrName key(prev().sv());
-            consume(TK("="));
+            consume(TK_ASSIGN);
             check(EXPR());
             e->kwargs.push_back({key, ctx()->s_popx()});
         } else {
@@ -487,8 +487,8 @@ Error* Compiler::exprCall() noexcept{
             }
         }
         check_newlines_repl()
-    } while(match(TK(",")));
-    consume(TK(")"));
+    } while(match(TK_COMMA));
+    consume(TK_RPAREN);
     return NULL;
 }
 
@@ -501,7 +501,7 @@ Error* Compiler::exprName() noexcept{
 }
 
 Error* Compiler::exprAttrib() noexcept{
-    consume(TK("@id"));
+    consume(TK_ID);
     ctx()->s_push(make_expr<AttribExpr>(ctx()->s_popx(), StrName::get(prev().sv())));
     return NULL;
 }
@@ -514,11 +514,11 @@ Error* Compiler::exprSlice0() noexcept{
         check(EXPR());
         slice->stop = ctx()->s_popx();
         // try optional step
-        if(match(TK(":"))) {  // :<stop>:<step>
+        if(match(TK_COLON)) {  // :<stop>:<step>
             check(EXPR());
             slice->step = ctx()->s_popx();
         }
-    } else if(match(TK(":"))) {
+    } else if(match(TK_COLON)) {
         if(is_expression()) {  // ::<step>
             check(EXPR());
             slice->step = ctx()->s_popx();
@@ -536,11 +536,11 @@ Error* Compiler::exprSlice1() noexcept{
         check(EXPR());
         slice->stop = ctx()->s_popx();
         // try optional step
-        if(match(TK(":"))) {  // <start>:<stop>:<step>
+        if(match(TK_COLON)) {  // <start>:<stop>:<step>
             check(EXPR());
             slice->step = ctx()->s_popx();
         }
-    } else if(match(TK(":"))) {  // <start>::<step>
+    } else if(match(TK_COLON)) {  // <start>::<step>
         check(EXPR());
         slice->step = ctx()->s_popx();
     }  // else <start>:
@@ -553,7 +553,7 @@ Error* Compiler::exprSubscr() noexcept{
     check_newlines_repl()
     check(EXPR_TUPLE(true));
     check_newlines_repl()
-    consume(TK("]"));           // [lhs, rhs]
+    consume(TK_RBRACKET);           // [lhs, rhs]
     SubscrExpr* e = make_expr<SubscrExpr>();
     e->line = line;
     e->rhs = ctx()->s_popx();   // [lhs]
@@ -570,12 +570,12 @@ Error* Compiler::exprLiteral0() noexcept{
 Error* Compiler::compile_block_body(PrattCallback callback) noexcept{
     Error* err;
     if(!callback) callback = &Compiler::compile_stmt;
-    consume(TK(":"));
-    if(curr().type != TK("@eol") && curr().type != TK("@eof")) {
+    consume(TK_COLON);
+    if(curr().type != TK_EOL && curr().type != TK_EOF) {
         while(true) {
             check(compile_stmt());
-            bool possible = curr().type != TK("@eol") && curr().type != TK("@eof");
-            if(prev().type != TK(";") || !possible) break;
+            bool possible = curr().type != TK_EOL && curr().type != TK_EOF;
+            if(prev().type != TK_SEMICOLON || !possible) break;
         }
         return NULL;
     }
@@ -585,13 +585,13 @@ Error* Compiler::compile_block_body(PrattCallback callback) noexcept{
     if(need_more_lines) return NeedMoreLines();
     if(!consumed) return SyntaxError("expected a new line after ':'");
 
-    consume(TK("@indent"));
-    while(curr().type != TK("@dedent")) {
+    consume(TK_INDENT);
+    while(curr().type != TK_DEDENT) {
         match_newlines();
         check((this->*callback)());
         match_newlines();
     }
-    consume(TK("@dedent"));
+    consume(TK_DEDENT);
     return NULL;
 }
 
@@ -599,15 +599,15 @@ Error* Compiler::compile_block_body(PrattCallback callback) noexcept{
 // import a [as b], c [as d]
 Error* Compiler::compile_normal_import() noexcept{
     do {
-        consume(TK("@id"));
+        consume(TK_ID);
         Str name = prev().str();
         ctx()->emit_(OP_IMPORT_PATH, ctx()->add_const_string(name.sv()), prev().line);
-        if(match(TK("as"))) {
-            consume(TK("@id"));
+        if(match(TK_AS)) {
+            consume(TK_ID);
             name = prev().str();
         }
         ctx()->emit_store_name(name_scope(), StrName(name), prev().line);
-    } while(match(TK(",")));
+    } while(match(TK_COMMA));
     consume_end_stmt();
     return NULL;
 }
@@ -624,9 +624,9 @@ Error* Compiler::compile_from_import() noexcept{
 
     while(true) {
         switch(curr().type) {
-            case TK("."): dots += 1; break;
-            case TK(".."): dots += 2; break;
-            case TK("..."): dots += 3; break;
+            case TK_DOT: dots += 1; break;
+            case TK_DOTDOT: dots += 2; break;
+            case TK_DOTDOTDOT: dots += 3; break;
             default: goto __EAT_DOTS_END;
         }
         advance();
@@ -638,27 +638,27 @@ __EAT_DOTS_END:
 
     if(dots > 0) {
         // @id is optional if dots > 0
-        if(match(TK("@id"))) {
+        if(match(TK_ID)) {
             ss << prev().sv();
-            while(match(TK("."))) {
-                consume(TK("@id"));
+            while(match(TK_DOT)) {
+                consume(TK_ID);
                 ss << "." << prev().sv();
             }
         }
     } else {
         // @id is required if dots == 0
-        consume(TK("@id"));
+        consume(TK_ID);
         ss << prev().sv();
-        while(match(TK("."))) {
-            consume(TK("@id"));
+        while(match(TK_DOT)) {
+            consume(TK_ID);
             ss << "." << prev().sv();
         }
     }
 
     ctx()->emit_(OP_IMPORT_PATH, ctx()->add_const_string(ss.str().sv()), prev().line);
-    consume(TK("import"));
+    consume(TK_IMPORT);
 
-    if(match(TK("*"))) {
+    if(match(TK_MUL)) {
         if(name_scope() != NAME_GLOBAL) return SyntaxError("from <module> import * can only be used in global scope");
         // pop the module and import __all__
         ctx()->emit_(OP_POP_IMPORT_STAR, BC_NOARG, prev().line);
@@ -668,15 +668,15 @@ __EAT_DOTS_END:
 
     do {
         ctx()->emit_(OP_DUP_TOP, BC_NOARG, BC_KEEPLINE);
-        consume(TK("@id"));
+        consume(TK_ID);
         Str name = prev().str();
         ctx()->emit_(OP_LOAD_ATTR, StrName(name).index, prev().line);
-        if(match(TK("as"))) {
-            consume(TK("@id"));
+        if(match(TK_AS)) {
+            consume(TK_ID);
             name = prev().str();
         }
         ctx()->emit_store_name(name_scope(), StrName(name), prev().line);
-    } while(match(TK(",")));
+    } while(match(TK_COMMA));
     ctx()->emit_(OP_POP_TOP, BC_NOARG, BC_KEEPLINE);
     consume_end_stmt();
     return NULL;
@@ -684,18 +684,18 @@ __EAT_DOTS_END:
 
 bool Compiler::is_expression(bool allow_slice) noexcept{
     PrattCallback prefix = rules[curr().type].prefix;
-    return prefix != nullptr && (allow_slice || curr().type != TK(":"));
+    return prefix != nullptr && (allow_slice || curr().type != TK_COLON);
 }
 
 Error* Compiler::parse_expression(int precedence, bool allow_slice) noexcept{
     PrattCallback prefix = rules[curr().type].prefix;
-    if(prefix == nullptr || (curr().type == TK(":") && !allow_slice)) {
-        return SyntaxError("expected an expression, got %s", TK_STR(curr().type));
+    if(prefix == nullptr || (curr().type == TK_COLON && !allow_slice)) {
+        return SyntaxError("expected an expression, got %s", pk_TokenSymbols[curr().type]);
     }
     advance();
     Error* err;
     check((this->*prefix)());
-    while(rules[curr().type].precedence >= precedence && (allow_slice || curr().type != TK(":"))) {
+    while(rules[curr().type].precedence >= precedence && (allow_slice || curr().type != TK_COLON)) {
         TokenIndex op = curr().type;
         advance();
         PrattCallback infix = rules[op].infix;
@@ -712,12 +712,12 @@ Error* Compiler::compile_if_stmt() noexcept{
     int patch = ctx()->emit_(OP_POP_JUMP_IF_FALSE, BC_NOARG, prev().line);
     err = compile_block_body();
     if(err) return err;
-    if(match(TK("elif"))) {
+    if(match(TK_ELIF)) {
         int exit_patch = ctx()->emit_(OP_JUMP_FORWARD, BC_NOARG, prev().line);
         ctx()->patch_jump(patch);
         check(compile_if_stmt());
         ctx()->patch_jump(exit_patch);
-    } else if(match(TK("else"))) {
+    } else if(match(TK_ELSE)) {
         int exit_patch = ctx()->emit_(OP_JUMP_FORWARD, BC_NOARG, prev().line);
         ctx()->patch_jump(patch);
         check(compile_block_body());
@@ -739,7 +739,7 @@ Error* Compiler::compile_while_loop() noexcept{
     ctx()->patch_jump(patch);
     ctx()->exit_block();
     // optional else clause
-    if(match(TK("else"))) {
+    if(match(TK_ELSE)) {
         check(compile_block_body());
         block->end2 = ctx()->co->codes.size();
     }
@@ -749,7 +749,7 @@ Error* Compiler::compile_while_loop() noexcept{
 Error* Compiler::compile_for_loop() noexcept{
     Error* err;
     check(EXPR_VARS());     // [vars]
-    consume(TK("in"));
+    consume(TK_IN);
     check(EXPR_TUPLE());    // [vars, iter]
     ctx()->s_emit_top();     // [vars]
     ctx()->emit_(OP_GET_ITER_NEW, BC_NOARG, BC_KEEPLINE);
@@ -764,7 +764,7 @@ Error* Compiler::compile_for_loop() noexcept{
     ctx()->emit_(OP_LOOP_CONTINUE, ctx()->get_loop(), BC_KEEPLINE, true);
     ctx()->exit_block();
     // optional else clause
-    if(match(TK("else"))) {
+    if(match(TK_ELSE)) {
         check(compile_block_body());
         block->end2 = ctx()->co->codes.size();
     }
@@ -781,16 +781,16 @@ Error* Compiler::compile_try_except() noexcept{
     ctx()->exit_block();
 
     int finally_entry = -1;
-    if(curr().type != TK("finally")) {
+    if(curr().type != TK_FINALLY) {
         do {
             StrName as_name;
-            consume(TK("except"));
+            consume(TK_EXCEPT);
             if(is_expression()) {
                 check(EXPR());  // push assumed type on to the stack
                 ctx()->s_emit_top();
                 ctx()->emit_(OP_EXCEPTION_MATCH, BC_NOARG, prev().line);
-                if(match(TK("as"))) {
-                    consume(TK("@id"));
+                if(match(TK_AS)) {
+                    consume(TK_ID);
                     as_name = StrName(prev().sv());
                 }
             } else {
@@ -807,10 +807,10 @@ Error* Compiler::compile_try_except() noexcept{
             check(compile_block_body());
             patches.push_back(ctx()->emit_(OP_JUMP_FORWARD, BC_NOARG, BC_KEEPLINE));
             ctx()->patch_jump(patch);
-        } while(curr().type == TK("except"));
+        } while(curr().type == TK_EXCEPT);
     }
 
-    if(match(TK("finally"))) {
+    if(match(TK_FINALLY)) {
         int patch = ctx()->emit_(OP_JUMP_FORWARD, BC_NOARG, BC_KEEPLINE);
         finally_entry = ctx()->co->codes.size();
         check(compile_block_body());
@@ -848,12 +848,12 @@ Error* Compiler::compile_decorated() noexcept{
         bool consumed = match_newlines(&need_more_lines);
         if(need_more_lines) return NeedMoreLines();
         if(!consumed) return SyntaxError("expected a newline after '@'");
-    } while(match(TK("@")));
+    } while(match(TK_DECORATOR));
 
-    if(match(TK("class"))) {
+    if(match(TK_CLASS)) {
         check(compile_class(count));
     } else {
-        consume(TK("def"));
+        consume(TK_DEF);
         check(compile_function(count));
     }
     return NULL;
@@ -862,17 +862,17 @@ Error* Compiler::compile_decorated() noexcept{
 Error* Compiler::try_compile_assignment(bool* is_assign) noexcept{
     Error* err;
     switch(curr().type) {
-        case TK("+="):
-        case TK("-="):
-        case TK("*="):
-        case TK("/="):
-        case TK("//="):
-        case TK("%="):
-        case TK("<<="):
-        case TK(">>="):
-        case TK("&="):
-        case TK("|="):
-        case TK("^="): {
+        case TK_IADD:
+        case TK_ISUB:
+        case TK_IMUL:
+        case TK_IDIV:
+        case TK_IFLOORDIV:
+        case TK_IMOD:
+        case TK_ILSHIFT:
+        case TK_IRSHIFT:
+        case TK_IAND:
+        case TK_IOR:
+        case TK_IXOR: {
             if(ctx()->s_top()->is_starred()) return SyntaxError();
             if(ctx()->is_compiling_class){
                 return SyntaxError("can't use inplace operator in class definition");
@@ -882,7 +882,7 @@ Error* Compiler::try_compile_assignment(bool* is_assign) noexcept{
             // a.x += 1;    a should be evaluated only once
             // -1 to remove =; inplace=true
             int line = prev().line;
-            TokenIndex op = prev().type-1;
+            TokenIndex op = (TokenIndex)(prev().type - 1);
             // [lhs]
             check(EXPR_TUPLE());        // [lhs, rhs]
             if(ctx()->s_top()->is_starred()) return SyntaxError();
@@ -897,9 +897,9 @@ Error* Compiler::try_compile_assignment(bool* is_assign) noexcept{
             *is_assign = true;
             return NULL;
         }
-        case TK("="): {
+        case TK_ASSIGN: {
             int n = 0;
-            while(match(TK("="))) {
+            while(match(TK_ASSIGN)) {
                 check(EXPR_TUPLE());
                 n += 1;
             }
@@ -923,7 +923,7 @@ Error* Compiler::try_compile_assignment(bool* is_assign) noexcept{
 
 Error* Compiler::compile_stmt() noexcept{
     Error* err;
-    if(match(TK("class"))) {
+    if(match(TK_CLASS)) {
         check(compile_class());
         return NULL;
     }
@@ -931,24 +931,24 @@ Error* Compiler::compile_stmt() noexcept{
     int kw_line = prev().line;  // backup line number
     int curr_loop_block = ctx()->get_loop();
     switch(prev().type) {
-        case TK("break"):
+        case TK_BREAK:
             if(curr_loop_block < 0) return SyntaxError("'break' outside loop");
             ctx()->emit_(OP_LOOP_BREAK, curr_loop_block, kw_line);
             consume_end_stmt();
             break;
-        case TK("continue"):
+        case TK_CONTINUE:
             if(curr_loop_block < 0) return SyntaxError("'continue' not properly in loop");
             ctx()->emit_(OP_LOOP_CONTINUE, curr_loop_block, kw_line);
             consume_end_stmt();
             break;
-        case TK("yield"):
+        case TK_YIELD:
             if(contexts.size() <= 1) return SyntaxError("'yield' outside function");
             check(EXPR_TUPLE());
             ctx()->s_emit_top();
             ctx()->emit_(OP_YIELD_VALUE, BC_NOARG, kw_line);
             consume_end_stmt();
             break;
-        case TK("yield from"):
+        case TK_YIELD_FROM:
             if(contexts.size() <= 1) return SyntaxError("'yield from' outside function");
             check(EXPR_TUPLE());
             ctx()->s_emit_top();
@@ -960,7 +960,7 @@ Error* Compiler::compile_stmt() noexcept{
             ctx()->exit_block();
             consume_end_stmt();
             break;
-        case TK("return"):
+        case TK_RETURN:
             if(contexts.size() <= 1) return SyntaxError("'return' outside function");
             if(match_end_stmt()) {
                 ctx()->emit_(OP_RETURN_VALUE, 1, kw_line);
@@ -972,22 +972,22 @@ Error* Compiler::compile_stmt() noexcept{
             }
             break;
         /*************************************************/
-        case TK("if"): check(compile_if_stmt()); break;
-        case TK("while"): check(compile_while_loop()); break;
-        case TK("for"): check(compile_for_loop()); break;
-        case TK("import"): check(compile_normal_import()); break;
-        case TK("from"): check(compile_from_import()); break;
-        case TK("def"): check(compile_function()); break;
-        case TK("@"): check(compile_decorated()); break;
-        case TK("try"): check(compile_try_except()); break;
-        case TK("pass"): consume_end_stmt(); break;
+        case TK_IF: check(compile_if_stmt()); break;
+        case TK_WHILE: check(compile_while_loop()); break;
+        case TK_FOR: check(compile_for_loop()); break;
+        case TK_IMPORT: check(compile_normal_import()); break;
+        case TK_FROM: check(compile_from_import()); break;
+        case TK_DEF: check(compile_function()); break;
+        case TK_DECORATOR: check(compile_decorated()); break;
+        case TK_TRY: check(compile_try_except()); break;
+        case TK_PASS: consume_end_stmt(); break;
         /*************************************************/
-        case TK("assert"): {
+        case TK_ASSERT: {
             check(EXPR());  // condition
             ctx()->s_emit_top();
             int index = ctx()->emit_(OP_POP_JUMP_IF_TRUE, BC_NOARG, kw_line);
             int has_msg = 0;
-            if(match(TK(","))) {
+            if(match(TK_COMMA)) {
                 check(EXPR());  // message
                 ctx()->s_emit_top();
                 has_msg = 1;
@@ -997,32 +997,32 @@ Error* Compiler::compile_stmt() noexcept{
             consume_end_stmt();
             break;
         }
-        case TK("global"):
+        case TK_GLOBAL:
             do {
-                consume(TK("@id"));
+                consume(TK_ID);
                 ctx()->global_names.push_back(StrName(prev().sv()));
-            } while(match(TK(",")));
+            } while(match(TK_COMMA));
             consume_end_stmt();
             break;
-        case TK("raise"): {
+        case TK_RAISE: {
             check(EXPR());
             ctx()->s_emit_top();
             ctx()->emit_(OP_RAISE, BC_NOARG, kw_line);
             consume_end_stmt();
         } break;
-        case TK("del"): {
+        case TK_DEL: {
             check(EXPR_TUPLE());
             if(!ctx()->s_top()->emit_del(ctx())) return SyntaxError();
             ctx()->s_pop();
             consume_end_stmt();
         } break;
-        case TK("with"): {
+        case TK_WITH: {
             check(EXPR());  // [ <expr> ]
             ctx()->s_emit_top();
             ctx()->enter_block(CodeBlockType::CONTEXT_MANAGER);
             Expr* as_name = nullptr;
-            if(match(TK("as"))) {
-                consume(TK("@id"));
+            if(match(TK_AS)) {
+                consume(TK_ID);
                 as_name = make_expr<NameExpr>(prev().str(), name_scope());
             }
             ctx()->emit_(OP_WITH_ENTER, BC_NOARG, prev().line);
@@ -1039,18 +1039,18 @@ Error* Compiler::compile_stmt() noexcept{
             ctx()->exit_block();
         } break;
         /*************************************************/
-        case TK("=="): {
-            consume(TK("@id"));
+        case TK_EQ: {
+            consume(TK_ID);
             if(mode() != EXEC_MODE) return SyntaxError("'label' is only available in EXEC_MODE");
             if(!ctx()->add_label(prev().str())) {
                 Str escaped(prev().str().escape());
                 return SyntaxError("label %s already exists", escaped.c_str());
             }
-            consume(TK("=="));
+            consume(TK_EQ);
             consume_end_stmt();
         } break;
-        case TK("->"):
-            consume(TK("@id"));
+        case TK_ARROW:
+            consume(TK_ID);
             if(mode() != EXEC_MODE) return SyntaxError("'goto' is only available in EXEC_MODE");
             ctx()->emit_(OP_GOTO, StrName(prev().sv()).index, prev().line);
             consume_end_stmt();
@@ -1064,7 +1064,7 @@ Error* Compiler::compile_stmt() noexcept{
             bool is_typed_name = false;  // e.g. x: int
             // eat variable's type hint if it is a single name
             if(ctx()->s_top()->is_name()) {
-                if(match(TK(":"))) {
+                if(match(TK_COLON)) {
                     check(consume_type_hints());
                     is_typed_name = true;
 
@@ -1107,15 +1107,15 @@ Error* Compiler::consume_type_hints() noexcept{
 
 Error* Compiler::compile_class(int decorators) noexcept{
     Error* err;
-    consume(TK("@id"));
+    consume(TK_ID);
     int namei = StrName(prev().sv()).index;
     bool has_base = false;
-    if(match(TK("("))) {
+    if(match(TK_LPAREN)) {
         if(is_expression()) {
             check(EXPR());
             has_base = true;    // [base]
         }
-        consume(TK(")"));
+        consume(TK_RPAREN);
     }
     if(!has_base) {
         ctx()->emit_(OP_LOAD_NONE, BC_NOARG, prev().line);
@@ -1148,15 +1148,15 @@ Error* Compiler::_compile_f_args(FuncDecl_ decl, bool enable_type_hints) noexcep
         if(state > 3) return SyntaxError();
         if(state == 3) return SyntaxError("**kwargs should be the last argument");
         match_newlines();
-        if(match(TK("*"))) {
+        if(match(TK_MUL)) {
             if(state < 1)
                 state = 1;
             else
                 return SyntaxError("*args should be placed before **kwargs");
-        } else if(match(TK("**"))) {
+        } else if(match(TK_POW)) {
             state = 3;
         }
-        consume(TK("@id"));
+        consume(TK_ID);
         StrName name(prev().sv());
 
         // check duplicate argument name
@@ -1174,8 +1174,8 @@ Error* Compiler::_compile_f_args(FuncDecl_ decl, bool enable_type_hints) noexcep
         }
 
         // eat type hints
-        if(enable_type_hints && match(TK(":"))) check(consume_type_hints());
-        if(state == 0 && curr().type == TK("=")) state = 2;
+        if(enable_type_hints && match(TK_COLON)) check(consume_type_hints());
+        if(state == 0 && curr().type == TK_ASSIGN) state = 2;
         int index = ctx()->add_varname(name);
         switch(state) {
             case 0: decl->args.push_back(index); break;
@@ -1184,7 +1184,7 @@ Error* Compiler::_compile_f_args(FuncDecl_ decl, bool enable_type_hints) noexcep
                 state += 1;
                 break;
             case 2: {
-                consume(TK("="));
+                consume(TK_ASSIGN);
                 PyVar value;
                 check(read_literal(&value));
                 if(value == nullptr) return SyntaxError("default argument must be a literal");
@@ -1195,21 +1195,21 @@ Error* Compiler::_compile_f_args(FuncDecl_ decl, bool enable_type_hints) noexcep
                 state += 1;
                 break;
         }
-    } while(match(TK(",")));
+    } while(match(TK_COMMA));
     return NULL;
 }
 
 Error* Compiler::compile_function(int decorators) noexcept{
     Error* err;
-    consume(TK("@id"));
+    consume(TK_ID);
     Str decl_name = prev().str();
     FuncDecl_ decl = push_f_context(decl_name);
-    consume(TK("("));
-    if(!match(TK(")"))) {
+    consume(TK_LPAREN);
+    if(!match(TK_RPAREN)) {
         check(_compile_f_args(decl, true));
-        consume(TK(")"));
+        consume(TK_RPAREN);
     }
-    if(match(TK("->"))) check(consume_type_hints());
+    if(match(TK_ARROW)) check(consume_type_hints());
     check(compile_block_body());
     check(pop_context());
 
@@ -1251,29 +1251,29 @@ Error* Compiler::read_literal(PyVar* out) noexcept{
     Error* err;
     advance();
     switch(prev().type) {
-        case TK("-"): {
-            consume(TK("@num"));
+        case TK_SUB: {
+            consume(TK_NUM);
             PyVar val = to_object(prev().value);
             *out = vm->py_negate(val);
             return NULL;
         }
-        case TK("@num"): *out = to_object(prev().value); return NULL;
-        case TK("@str"): *out = to_object(prev().value); return NULL;
-        case TK("True"): *out = VAR(true);  return NULL;
-        case TK("False"): *out = VAR(false); return NULL;
-        case TK("None"): *out = vm->None; return NULL;
-        case TK("..."): *out = vm->Ellipsis; return NULL;
-        case TK("("): {
+        case TK_NUM: *out = to_object(prev().value); return NULL;
+        case TK_STR: *out = to_object(prev().value); return NULL;
+        case TK_TRUE: *out = VAR(true);  return NULL;
+        case TK_FALSE: *out = VAR(false); return NULL;
+        case TK_NONE: *out = vm->None; return NULL;
+        case TK_DOTDOTDOT: *out = vm->Ellipsis; return NULL;
+        case TK_LPAREN: {
             List cpnts;
             while(true) {
                 PyVar elem;
                 check(read_literal(&elem));
                 cpnts.push_back(elem);
-                if(curr().type == TK(")")) break;
-                consume(TK(","));
-                if(curr().type == TK(")")) break;
+                if(curr().type == TK_RPAREN) break;
+                consume(TK_COMMA);
+                if(curr().type == TK_RPAREN) break;
             }
-            consume(TK(")"));
+            consume(TK_RPAREN);
             *out = VAR(cpnts.to_tuple());
             return NULL;
         }
@@ -1297,20 +1297,20 @@ Error* Compiler::compile(CodeObject_* out) noexcept{
     // if(lexer.src.filename()[0] != '<'){
     //     printf("%s\n", lexer.src.filename().c_str());
     //     for(int i=0; i<lexer.nexts.size(); i++){
-    //         printf("%s: %s\n", TK_STR(tk(i).type), tk(i).str().escape().c_str());
+    //         printf("%s: %s\n", pk_TokenSymbols[tk(i).type], tk(i).str().escape().c_str());
     //     }
     // }
 
     CodeObject_ code = push_global_context();
 
-    assert(curr().type == TK("@sof"));
+    assert(curr().type == TK_SOF);
     advance();         // skip @sof, so prev() is always valid
     match_newlines();  // skip possible leading '\n'
 
     if(mode() == EVAL_MODE) {
         check(EXPR_TUPLE());
         ctx()->s_emit_top();
-        consume(TK("@eof"));
+        consume(TK_EOF);
         ctx()->emit_(OP_RETURN_VALUE, BC_NOARG, BC_KEEPLINE);
         check(pop_context());
         *out = code;
@@ -1319,7 +1319,7 @@ Error* Compiler::compile(CodeObject_* out) noexcept{
         check(EXPR());
         Expr* e = ctx()->s_popx();
         if(!e->is_json_object()) return SyntaxError("expect a JSON object, literal or array");
-        consume(TK("@eof"));
+        consume(TK_EOF);
         e->emit_(ctx());
         ctx()->emit_(OP_RETURN_VALUE, BC_NOARG, BC_KEEPLINE);
         check(pop_context());
@@ -1327,7 +1327,7 @@ Error* Compiler::compile(CodeObject_* out) noexcept{
         return NULL;
     }
 
-    while(!match(TK("@eof"))) {
+    while(!match(TK_EOF)) {
         check(compile_stmt());
         match_newlines();
     }
diff --git a/src/compiler/expr.cpp b/src/compiler/expr.cpp
index 18ca583f..aa09921d 100644
--- a/src/compiler/expr.cpp
+++ b/src/compiler/expr.cpp
@@ -231,10 +231,10 @@ void OrExpr::emit_(CodeEmitContext* ctx) {
 
 void Literal0Expr::emit_(CodeEmitContext* ctx) {
     switch(token) {
-        case TK("None"): ctx->emit_(OP_LOAD_NONE, BC_NOARG, line); break;
-        case TK("True"): ctx->emit_(OP_LOAD_TRUE, BC_NOARG, line); break;
-        case TK("False"): ctx->emit_(OP_LOAD_FALSE, BC_NOARG, line); break;
-        case TK("..."): ctx->emit_(OP_LOAD_ELLIPSIS, BC_NOARG, line); break;
+        case TK_NONE: ctx->emit_(OP_LOAD_NONE, BC_NOARG, line); break;
+        case TK_TRUE: ctx->emit_(OP_LOAD_TRUE, BC_NOARG, line); break;
+        case TK_FALSE: ctx->emit_(OP_LOAD_FALSE, BC_NOARG, line); break;
+        case TK_DOTDOTDOT: ctx->emit_(OP_LOAD_ELLIPSIS, BC_NOARG, line); break;
         default: assert(false);
     }
 }
@@ -681,12 +681,12 @@ void CallExpr::emit_(CodeEmitContext* ctx) {
 
 bool BinaryExpr::is_compare() const {
     switch(op) {
-        case TK("<"):
-        case TK("<="):
-        case TK("=="):
-        case TK("!="):
-        case TK(">"):
-        case TK(">="): return true;
+        case TK_LT:
+        case TK_LE:
+        case TK_EQ:
+        case TK_NE:
+        case TK_GT:
+        case TK_GE: return true;
         default: return false;
     }
 }
@@ -701,12 +701,12 @@ void BinaryExpr::_emit_compare(CodeEmitContext* ctx, small_vector_2<int, 8>& jmp
     ctx->emit_(OP_DUP_TOP, BC_NOARG, line);    // [a, b, b]
     ctx->emit_(OP_ROT_THREE, BC_NOARG, line);  // [b, a, b]
     switch(op) {
-        case TK("<"): ctx->emit_(OP_COMPARE_LT, BC_NOARG, line); break;
-        case TK("<="): ctx->emit_(OP_COMPARE_LE, BC_NOARG, line); break;
-        case TK("=="): ctx->emit_(OP_COMPARE_EQ, BC_NOARG, line); break;
-        case TK("!="): ctx->emit_(OP_COMPARE_NE, BC_NOARG, line); break;
-        case TK(">"): ctx->emit_(OP_COMPARE_GT, BC_NOARG, line); break;
-        case TK(">="): ctx->emit_(OP_COMPARE_GE, BC_NOARG, line); break;
+        case TK_LT: ctx->emit_(OP_COMPARE_LT, BC_NOARG, line); break;
+        case TK_LE: ctx->emit_(OP_COMPARE_LE, BC_NOARG, line); break;
+        case TK_EQ: ctx->emit_(OP_COMPARE_EQ, BC_NOARG, line); break;
+        case TK_NE: ctx->emit_(OP_COMPARE_NE, BC_NOARG, line); break;
+        case TK_GT: ctx->emit_(OP_COMPARE_GT, BC_NOARG, line); break;
+        case TK_GE: ctx->emit_(OP_COMPARE_GE, BC_NOARG, line); break;
         default: PK_UNREACHABLE()
     }
     // [b, RES]
@@ -731,34 +731,34 @@ void BinaryExpr::emit_(CodeEmitContext* ctx) {
 
     rhs->emit_(ctx);
     switch(op) {
-        case TK("+"): ctx->emit_(OP_BINARY_ADD, BC_NOARG, line); break;
-        case TK("-"): ctx->emit_(OP_BINARY_SUB, BC_NOARG, line); break;
-        case TK("*"): ctx->emit_(OP_BINARY_MUL, BC_NOARG, line); break;
-        case TK("/"): ctx->emit_(OP_BINARY_TRUEDIV, BC_NOARG, line); break;
-        case TK("//"): ctx->emit_(OP_BINARY_FLOORDIV, BC_NOARG, line); break;
-        case TK("%"): ctx->emit_(OP_BINARY_MOD, BC_NOARG, line); break;
-        case TK("**"): ctx->emit_(OP_BINARY_POW, BC_NOARG, line); break;
+        case TK_ADD: ctx->emit_(OP_BINARY_ADD, BC_NOARG, line); break;
+        case TK_SUB: ctx->emit_(OP_BINARY_SUB, BC_NOARG, line); break;
+        case TK_MUL: ctx->emit_(OP_BINARY_MUL, BC_NOARG, line); break;
+        case TK_DIV: ctx->emit_(OP_BINARY_TRUEDIV, BC_NOARG, line); break;
+        case TK_FLOORDIV: ctx->emit_(OP_BINARY_FLOORDIV, BC_NOARG, line); break;
+        case TK_MOD: ctx->emit_(OP_BINARY_MOD, BC_NOARG, line); break;
+        case TK_POW: ctx->emit_(OP_BINARY_POW, BC_NOARG, line); break;
 
-        case TK("<"): ctx->emit_(OP_COMPARE_LT, BC_NOARG, line); break;
-        case TK("<="): ctx->emit_(OP_COMPARE_LE, BC_NOARG, line); break;
-        case TK("=="): ctx->emit_(OP_COMPARE_EQ, BC_NOARG, line); break;
-        case TK("!="): ctx->emit_(OP_COMPARE_NE, BC_NOARG, line); break;
-        case TK(">"): ctx->emit_(OP_COMPARE_GT, BC_NOARG, line); break;
-        case TK(">="): ctx->emit_(OP_COMPARE_GE, BC_NOARG, line); break;
+        case TK_LT: ctx->emit_(OP_COMPARE_LT, BC_NOARG, line); break;
+        case TK_LE: ctx->emit_(OP_COMPARE_LE, BC_NOARG, line); break;
+        case TK_EQ: ctx->emit_(OP_COMPARE_EQ, BC_NOARG, line); break;
+        case TK_NE: ctx->emit_(OP_COMPARE_NE, BC_NOARG, line); break;
+        case TK_GT: ctx->emit_(OP_COMPARE_GT, BC_NOARG, line); break;
+        case TK_GE: ctx->emit_(OP_COMPARE_GE, BC_NOARG, line); break;
 
-        case TK("in"): ctx->emit_(OP_CONTAINS_OP, 0, line); break;
-        case TK("not in"): ctx->emit_(OP_CONTAINS_OP, 1, line); break;
-        case TK("is"): ctx->emit_(OP_IS_OP, BC_NOARG, line); break;
-        case TK("is not"): ctx->emit_(OP_IS_NOT_OP, BC_NOARG, line); break;
+        case TK_IN: ctx->emit_(OP_CONTAINS_OP, 0, line); break;
+        case TK_NOT_IN: ctx->emit_(OP_CONTAINS_OP, 1, line); break;
+        case TK_IS: ctx->emit_(OP_IS_OP, BC_NOARG, line); break;
+        case TK_IS_NOT: ctx->emit_(OP_IS_NOT_OP, BC_NOARG, line); break;
 
-        case TK("<<"): ctx->emit_(OP_BITWISE_LSHIFT, BC_NOARG, line); break;
-        case TK(">>"): ctx->emit_(OP_BITWISE_RSHIFT, BC_NOARG, line); break;
-        case TK("&"): ctx->emit_(OP_BITWISE_AND, BC_NOARG, line); break;
-        case TK("|"): ctx->emit_(OP_BITWISE_OR, BC_NOARG, line); break;
-        case TK("^"): ctx->emit_(OP_BITWISE_XOR, BC_NOARG, line); break;
+        case TK_LSHIFT: ctx->emit_(OP_BITWISE_LSHIFT, BC_NOARG, line); break;
+        case TK_RSHIFT: ctx->emit_(OP_BITWISE_RSHIFT, BC_NOARG, line); break;
+        case TK_AND: ctx->emit_(OP_BITWISE_AND, BC_NOARG, line); break;
+        case TK_OR: ctx->emit_(OP_BITWISE_OR, BC_NOARG, line); break;
+        case TK_XOR: ctx->emit_(OP_BITWISE_XOR, BC_NOARG, line); break;
 
-        case TK("@"): ctx->emit_(OP_BINARY_MATMUL, BC_NOARG, line); break;
-        default: PK_FATAL_ERROR("unknown binary operator: %s\n", TK_STR(op));
+        case TK_DECORATOR: ctx->emit_(OP_BINARY_MATMUL, BC_NOARG, line); break;
+        default: PK_FATAL_ERROR("unknown binary operator: %s\n", pk_TokenSymbols[op]);
     }
 
     for(int i: jmps)
diff --git a/src/compiler/lexer.c b/src/compiler/lexer.c
index 9294b9cb..6db8486e 100644
--- a/src/compiler/lexer.c
+++ b/src/compiler/lexer.c
@@ -3,6 +3,30 @@
 #include "pocketpy/common/smallmap.h"
 #include "pocketpy/compiler/lexer.h"
 
+const char* pk_TokenSymbols[] = {
+    "@eof", "@eol", "@sof",
+    "@id", "@num", "@str", "@fstr", "@long", "@bytes", "@imag",
+    "@indent", "@dedent",
+    // These 3 are compound keywords which are generated on the fly
+    "is not", "not in", "yield from",
+    /*****************************************/
+    "+", "+=", "-", "-=",   // (INPLACE_OP - 1) can get '=' removed
+    "*", "*=", "/", "/=", "//", "//=", "%", "%=",
+    "&", "&=", "|", "|=", "^", "^=", 
+    "<<", "<<=", ">>", ">>=",
+    /*****************************************/
+    "(", ")", "[", "]", "{", "}",
+    ".", "..", "...", ",", ":", ";",
+    "**", "->", "#", "@",
+    ">", "<", "=", "==", "!=", ">=", "<=", "~",
+    /** KW_BEGIN **/
+    // NOTE: These keywords should be sorted in ascending order!!
+    "False", "None", "True", "and", "as", "assert", "break", "class", "continue",
+    "def", "del", "elif", "else", "except", "finally", "for", "from", "global",
+    "if", "import", "in", "is", "lambda", "not", "or", "pass", "raise", "return",
+    "try", "while", "with", "yield",
+};
+
 void pkpy_TokenDeserializer__ctor(pkpy_TokenDeserializer* self, const char* source){
     self->curr = source;
     self->source = source;
diff --git a/src/compiler/lexer.cpp b/src/compiler/lexer.cpp
index 40f66683..79a93ba5 100644
--- a/src/compiler/lexer.cpp
+++ b/src/compiler/lexer.cpp
@@ -62,11 +62,11 @@ bool Lexer::eat_indentation() noexcept{
     // https://docs.python.org/3/reference/lexical_analysis.html#indentation
     if(spaces > indents.back()) {
         indents.push_back(spaces);
-        nexts.push_back(Token{TK("@indent"), token_start, 0, current_line, brackets_level, {}});
+        nexts.push_back(Token{TK_INDENT, token_start, 0, current_line, brackets_level, {}});
     } else if(spaces < indents.back()) {
         while(spaces < indents.back()) {
             indents.pop_back();
-            nexts.push_back(Token{TK("@dedent"), token_start, 0, current_line, brackets_level, {}});
+            nexts.push_back(Token{TK_DEDENT, token_start, 0, current_line, brackets_level, {}});
         }
         if(spaces != indents.back()) { return false; }
     }
@@ -129,29 +129,32 @@ Error* Lexer::eat_name() noexcept{
 
     int length = (int)(curr_char - token_start);
     if(length == 0) return SyntaxError("@id contains invalid char");
-    std::string_view name(token_start, length);
+    c11_string name = {token_start, length};
 
     if(src->mode == JSON_MODE) {
-        if(name == "true") {
-            add_token(TK("True"));
-        } else if(name == "false") {
-            add_token(TK("False"));
-        } else if(name == "null") {
-            add_token(TK("None"));
+        if(c11_string__cmp3(name, "true") == 0) {
+            add_token(TK_TRUE);
+        } else if(c11_string__cmp3(name, "false") == 0) {
+            add_token(TK_FALSE);
+        } else if(c11_string__cmp3(name, "null") == 0) {
+            add_token(TK_NONE);
         } else {
             return SyntaxError("invalid JSON token");
         }
         return NULL;
     }
 
-    const auto KW_BEGIN = kTokens + TK("False");
-    const auto KW_END = kTokens + kTokenCount;
+    const char** KW_BEGIN = pk_TokenSymbols + TK_FALSE;
+    int KW_COUNT = TK__COUNT__ - TK_FALSE;
+    #define less(a, b) (c11_string__cmp3(b, a) > 0)
+    int out;
+    c11__lower_bound(const char*, KW_BEGIN, KW_COUNT, name, less, &out);
+    #undef less
 
-    auto it = lower_bound(KW_BEGIN, KW_END, name);
-    if(it != KW_END && *it == name) {
-        add_token(it - kTokens);
+    if(out != KW_COUNT && c11_string__cmp3(name, KW_BEGIN[out]) == 0) {
+        add_token((TokenIndex)(out + TK_FALSE));
     } else {
-        add_token(TK("@id"));
+        add_token(TK_ID);
     }
     return NULL;
 }
@@ -172,32 +175,33 @@ bool Lexer::matchchar(char c) noexcept{
 
 void Lexer::add_token(TokenIndex type, TokenValue value) noexcept{
     switch(type) {
-        case TK("{"):
-        case TK("["):
-        case TK("("): brackets_level++; break;
-        case TK(")"):
-        case TK("]"):
-        case TK("}"): brackets_level--; break;
+        case TK_LBRACE:
+        case TK_LBRACKET:
+        case TK_LPAREN: brackets_level++; break;
+        case TK_RPAREN:
+        case TK_RBRACKET:
+        case TK_RBRACE: brackets_level--; break;
+        default: break;
     }
     auto token = Token{type,
                        token_start,
                        (int)(curr_char - token_start),
-                       current_line - ((type == TK("@eol")) ? 1 : 0),
+                       current_line - ((type == TK_EOL) ? 1 : 0),
                        brackets_level,
                        value};
     // handle "not in", "is not", "yield from"
     if(!nexts.empty()) {
         auto& back = nexts.back();
-        if(back.type == TK("not") && type == TK("in")) {
-            back.type = TK("not in");
+        if(back.type == TK_NOT_KW && type == TK_IN) {
+            back.type = TK_NOT_IN;
             return;
         }
-        if(back.type == TK("is") && type == TK("not")) {
-            back.type = TK("is not");
+        if(back.type == TK_IS && type == TK_NOT_KW) {
+            back.type = TK_IS_NOT;
             return;
         }
-        if(back.type == TK("yield") && type == TK("from")) {
-            back.type = TK("yield from");
+        if(back.type == TK_YIELD && type == TK_FROM) {
+            back.type = TK_YIELD_FROM;
             return;
         }
         nexts.push_back(token);
@@ -271,11 +275,11 @@ Error* Lexer::eat_string(char quote, StringType type) noexcept{
     Error* err = eat_string_until(quote, type == StringType::RAW_STRING, &s);
     if(err) return err;
     if(type == StringType::F_STRING) {
-        add_token(TK("@fstr"), s);
+        add_token(TK_FSTR, s);
     }else if(type == StringType::NORMAL_BYTES) {
-        add_token(TK("@bytes"), s);
+        add_token(TK_BYTES, s);
     }else{
-        add_token(TK("@str"), s);
+        add_token(TK_STR, s);
     }
     return NULL;
 }
@@ -299,13 +303,13 @@ Error* Lexer::eat_number() noexcept{
     if(text[0] != '.' && !is_scientific_notation) {
         // try long
         if(i[-1] == 'L') {
-            add_token(TK("@long"));
+            add_token(TK_LONG);
             return NULL;
         }
         // try integer
         i64 int_out;
         switch(parse_uint(text, &int_out, -1)) {
-            case IntParsingResult::Success: add_token(TK("@num"), int_out); return NULL;
+            case IntParsingResult::Success: add_token(TK_NUM, int_out); return NULL;
             case IntParsingResult::Overflow: return SyntaxError("int literal is too large");
             case IntParsingResult::Failure: break;  // do nothing
         }
@@ -321,12 +325,12 @@ Error* Lexer::eat_number() noexcept{
     }
 
     if(p_end == text.data() + text.size()) {
-        add_token(TK("@num"), (f64)float_out);
+        add_token(TK_NUM, (f64)float_out);
         return NULL;
     }
 
     if(i[-1] == 'j' && p_end == text.data() + text.size() - 1) {
-        add_token(TK("@imag"), (f64)float_out);
+        add_token(TK_IMAG, (f64)float_out);
         return NULL;
     }
 
@@ -346,17 +350,17 @@ Error* Lexer::lex_one_token(bool* eof) noexcept{
                 return NULL;
             }
             case '#': skip_line_comment(); break;
-            case '~': add_token(TK("~")); return NULL;
-            case '{': add_token(TK("{")); return NULL;
-            case '}': add_token(TK("}")); return NULL;
-            case ',': add_token(TK(",")); return NULL;
-            case ':': add_token(TK(":")); return NULL;
-            case ';': add_token(TK(";")); return NULL;
-            case '(': add_token(TK("(")); return NULL;
-            case ')': add_token(TK(")")); return NULL;
-            case '[': add_token(TK("[")); return NULL;
-            case ']': add_token(TK("]")); return NULL;
-            case '@': add_token(TK("@")); return NULL;
+            case '~': add_token(TK_INVERT); return NULL;
+            case '{': add_token(TK_LBRACE); return NULL;
+            case '}': add_token(TK_RBRACE); return NULL;
+            case ',': add_token(TK_COMMA); return NULL;
+            case ':': add_token(TK_COLON); return NULL;
+            case ';': add_token(TK_SEMICOLON); return NULL;
+            case '(': add_token(TK_LPAREN); return NULL;
+            case ')': add_token(TK_RPAREN); return NULL;
+            case '[': add_token(TK_LBRACKET); return NULL;
+            case ']': add_token(TK_RBRACKET); return NULL;
+            case '@': add_token(TK_DECORATOR); return NULL;
             case '\\': {
                 // line continuation character
                 char c = eatchar_include_newline();
@@ -367,16 +371,16 @@ Error* Lexer::lex_one_token(bool* eof) noexcept{
                 eat_spaces();
                 return NULL;
             }
-            case '%': add_token_2('=', TK("%"), TK("%=")); return NULL;
-            case '&': add_token_2('=', TK("&"), TK("&=")); return NULL;
-            case '|': add_token_2('=', TK("|"), TK("|=")); return NULL;
-            case '^': add_token_2('=', TK("^"), TK("^=")); return NULL;
+            case '%': add_token_2('=', TK_MOD, TK_IMOD); return NULL;
+            case '&': add_token_2('=', TK_AND, TK_IAND); return NULL;
+            case '|': add_token_2('=', TK_OR, TK_IOR); return NULL;
+            case '^': add_token_2('=', TK_XOR, TK_IXOR); return NULL;
             case '.': {
                 if(matchchar('.')) {
                     if(matchchar('.')) {
-                        add_token(TK("..."));
+                        add_token(TK_DOTDOTDOT);
                     } else {
-                        add_token(TK(".."));
+                        add_token(TK_DOTDOT);
                     }
                 } else {
                     char next_char = peekchar();
@@ -384,43 +388,43 @@ Error* Lexer::lex_one_token(bool* eof) noexcept{
                         Error* err = eat_number();
                         if(err) return err;
                     } else {
-                        add_token(TK("."));
+                        add_token(TK_DOT);
                     }
                 }
                 return NULL;
             }
-            case '=': add_token_2('=', TK("="), TK("==")); return NULL;
-            case '+': add_token_2('=', TK("+"), TK("+=")); return NULL;
+            case '=': add_token_2('=', TK_ASSIGN, TK_EQ); return NULL;
+            case '+': add_token_2('=', TK_ADD, TK_IADD); return NULL;
             case '>': {
                 if(matchchar('='))
-                    add_token(TK(">="));
+                    add_token(TK_GE);
                 else if(matchchar('>'))
-                    add_token_2('=', TK(">>"), TK(">>="));
+                    add_token_2('=', TK_RSHIFT, TK_IRSHIFT);
                 else
-                    add_token(TK(">"));
+                    add_token(TK_GT);
                 return NULL;
             }
             case '<': {
                 if(matchchar('='))
-                    add_token(TK("<="));
+                    add_token(TK_LE);
                 else if(matchchar('<'))
-                    add_token_2('=', TK("<<"), TK("<<="));
+                    add_token_2('=', TK_LSHIFT, TK_ILSHIFT);
                 else
-                    add_token(TK("<"));
+                    add_token(TK_LT);
                 return NULL;
             }
             case '-': {
                 if(matchchar('='))
-                    add_token(TK("-="));
+                    add_token(TK_ISUB);
                 else if(matchchar('>'))
-                    add_token(TK("->"));
+                    add_token(TK_ARROW);
                 else
-                    add_token(TK("-"));
+                    add_token(TK_SUB);
                 return NULL;
             }
             case '!':
                 if(matchchar('=')){
-                    add_token(TK("!="));
+                    add_token(TK_NE);
                 }else{
                     Error* err = SyntaxError("expected '=' after '!'");
                     if(err) return err;
@@ -428,22 +432,22 @@ Error* Lexer::lex_one_token(bool* eof) noexcept{
                 break;
             case '*':
                 if(matchchar('*')) {
-                    add_token(TK("**"));  // '**'
+                    add_token(TK_POW);  // '**'
                 } else {
-                    add_token_2('=', TK("*"), TK("*="));
+                    add_token_2('=', TK_MUL, TK_IMUL);
                 }
                 return NULL;
             case '/':
                 if(matchchar('/')) {
-                    add_token_2('=', TK("//"), TK("//="));
+                    add_token_2('=', TK_FLOORDIV, TK_IFLOORDIV);
                 } else {
-                    add_token_2('=', TK("/"), TK("/="));
+                    add_token_2('=', TK_DIV, TK_IDIV);
                 }
                 return NULL;
             case ' ':
             case '\t': eat_spaces(); break;
             case '\n': {
-                add_token(TK("@eol"));
+                add_token(TK_EOL);
                 if(!eat_indentation()){
                     return IndentationError("unindent does not match any outer indentation level");
                 }
@@ -469,10 +473,10 @@ Error* Lexer::lex_one_token(bool* eof) noexcept{
     token_start = curr_char;
     while(indents.size() > 1) {
         indents.pop_back();
-        add_token(TK("@dedent"));
+        add_token(TK_DEDENT);
         return NULL;
     }
-    add_token(TK("@eof"));
+    add_token(TK_EOF);
     *eof = true;
     return NULL;
 }
@@ -496,7 +500,7 @@ Error* Lexer::_error(bool lexer_err, const char* type, const char* msg, va_list*
     if(args){
         vsnprintf(err->msg, sizeof(err->msg), msg, *args);
     }else{
-        std::strncpy(err->msg, msg, sizeof(err->msg));
+        strncpy(err->msg, msg, sizeof(err->msg));
     }
     err->userdata = userdata;
     return err;
@@ -517,7 +521,7 @@ Error* Lexer::run() noexcept{
         return from_precompiled();
     }
     // push initial tokens
-    this->nexts.push_back(Token{TK("@sof"), token_start, 0, current_line, brackets_level, {}});
+    this->nexts.push_back(Token{TK_SOF, token_start, 0, current_line, brackets_level, {}});
     this->indents.push_back(0);
 
     bool eof = false;
@@ -554,7 +558,7 @@ Error* Lexer::from_precompiled() noexcept{
     count = pkpy_TokenDeserializer__read_count(&deserializer);
     for(int i = 0; i < count; i++) {
         Token t;
-        t.type = (unsigned char)pkpy_TokenDeserializer__read_uint(&deserializer, ',');
+        t.type = (TokenIndex)pkpy_TokenDeserializer__read_uint(&deserializer, ',');
         if(is_raw_string_used(t.type)) {
             i64 index = pkpy_TokenDeserializer__read_uint(&deserializer, ',');
             pkpy_Str* p = c11__at(pkpy_Str, precompiled_tokens, index);
diff --git a/src/modules/random.cpp b/src/modules/random.cpp
index ad3942cd..02ac9bfc 100644
--- a/src/modules/random.cpp
+++ b/src/modules/random.cpp
@@ -201,6 +201,7 @@ struct Random {
                 f64 key = self.gen.uniform(0.0, cum_weights[size - 1]);
                 int index;
                 c11__lower_bound(f64, cum_weights.begin(), cum_weights.size(), key, c11__less, &index);
+                assert(index != cum_weights.size());
                 result[i] = data[index];
             }
             return VAR(std::move(result));