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[
  [:TkCLASS,      TkKW,  "class",  EXPR_CLASS],
  [:TkMODULE,     TkKW,  "module", EXPR_BEG],
  [:TkDEF,        TkKW,  "def",    EXPR_FNAME],
  [:TkUNDEF,      TkKW,  "undef",  EXPR_FNAME],
  [:TkBEGIN,      TkKW,  "begin",  EXPR_BEG],
  [:TkRESCUE,     TkKW,  "rescue", EXPR_MID],
  [:TkENSURE,     TkKW,  "ensure", EXPR_BEG],
  [:TkEND,        TkKW,  "end",    EXPR_END],
  [:TkIF,         TkKW,  "if",     EXPR_BEG, :TkIF_MOD],
  [:TkUNLESS,     TkKW,  "unless", EXPR_BEG, :TkUNLESS_MOD],
  [:TkTHEN,       TkKW,  "then",   EXPR_BEG],
  [:TkELSIF,      TkKW,  "elsif",  EXPR_BEG],
  [:TkELSE,       TkKW,  "else",   EXPR_BEG],
  [:TkCASE,       TkKW,  "case",   EXPR_BEG],
  [:TkWHEN,       TkKW,  "when",   EXPR_BEG],
  [:TkWHILE,      TkKW,  "while",  EXPR_BEG, :TkWHILE_MOD],
  [:TkUNTIL,      TkKW,  "until",  EXPR_BEG, :TkUNTIL_MOD],
  [:TkFOR,        TkKW,  "for",    EXPR_BEG],
  [:TkBREAK,      TkKW,  "break",  EXPR_END],
  [:TkNEXT,       TkKW,  "next",   EXPR_END],
  [:TkREDO,       TkKW,  "redo",   EXPR_END],
  [:TkRETRY,      TkKW,  "retry",  EXPR_END],
  [:TkIN,         TkKW,  "in",     EXPR_BEG],
  [:TkDO,         TkKW,  "do",     EXPR_BEG],
  [:TkRETURN,     TkKW,  "return", EXPR_MID],
  [:TkYIELD,      TkKW,  "yield",  EXPR_END],
  [:TkSUPER,      TkKW,  "super",  EXPR_END],
  [:TkSELF,       TkKW,  "self",   EXPR_END],
  [:TkNIL,        TkKW,  "nil",    EXPR_END],
  [:TkTRUE,       TkKW,  "true",   EXPR_END],
  [:TkFALSE,      TkKW,  "false",  EXPR_END],
  [:TkAND,        TkKW,  "and",    EXPR_BEG],
  [:TkOR,         TkKW,  "or",     EXPR_BEG],
  [:TkNOT,        TkKW,  "not",    EXPR_BEG],
  [:TkIF_MOD,     TkKW],
  [:TkUNLESS_MOD, TkKW],
  [:TkWHILE_MOD,  TkKW],
  [:TkUNTIL_MOD,  TkKW],
  [:TkALIAS,      TkKW,  "alias",    EXPR_FNAME],
  [:TkDEFINED,    TkKW,  "defined?", EXPR_END],
  [:TklBEGIN,     TkKW,  "BEGIN",    EXPR_END],
  [:TklEND,       TkKW,  "END",      EXPR_END],
  [:Tk__LINE__,   TkKW,  "__LINE__", EXPR_END],
  [:Tk__FILE__,   TkKW,  "__FILE__", EXPR_END],

  [:TkIDENTIFIER, TkId],
  [:TkFID,        TkId],
  [:TkGVAR,       TkId],
  [:TkIVAR,       TkId],
  [:TkCONSTANT,   TkId],

  [:TkINTEGER,    TkVal],
  [:TkFLOAT,      TkVal],
  [:TkSTRING,     TkVal],
  [:TkXSTRING,    TkVal],
  [:TkREGEXP,     TkVal],
  [:TkCOMMENT,    TkVal],

  [:TkDSTRING,    TkNode],
  [:TkDXSTRING,   TkNode],
  [:TkDREGEXP,    TkNode],
  [:TkNTH_REF,    TkId],
  [:TkBACK_REF,   TkId],

  [:TkUPLUS,      TkOp,   "+@"],
  [:TkUMINUS,     TkOp,   "-@"],
  [:TkPOW,        TkOp,   "**"],
  [:TkCMP,        TkOp,   "<=>"],
  [:TkEQ,         TkOp,   "=="],
  [:TkEQQ,        TkOp,   "==="],
  [:TkNEQ,        TkOp,   "!="],
  [:TkGEQ,        TkOp,   ">="],
  [:TkLEQ,        TkOp,   "<="],
  [:TkANDOP,      TkOp,   "&&"],
  [:TkOROP,       TkOp,   "||"],
  [:TkMATCH,      TkOp,   "=~"],
  [:TkNMATCH,     TkOp,   "!~"],
  [:TkDOT2,       TkOp,   ".."],
  [:TkDOT3,       TkOp,   "..."],
  [:TkAREF,       TkOp,   "[]"],
  [:TkASET,       TkOp,   "[]="],
  [:TkLSHFT,      TkOp,   "<<"],
  [:TkRSHFT,      TkOp,   ">>"],
  [:TkCOLON2,     TkOp],
  [:TkCOLON3,     TkOp],
#   [:OPASGN,       TkOp],               # +=, -=  etc. #
  [:TkASSOC,      TkOp,   "=>"],
  [:TkQUESTION,   TkOp,   "?"],        #?
  [:TkCOLON,      TkOp,   ":"],        #:

  [:TkfLPAREN],         # func( #
  [:TkfLBRACK],         # func[ #
  [:TkfLBRACE],         # func{ #
  [:TkSTAR],            # *arg
  [:TkAMPER],           # &arg #
  [:TkSYMBOL,     TkId],          # :SYMBOL
  [:TkSYMBEG,     TkId], 
  [:TkGT,         TkOp,   ">"],
  [:TkLT,         TkOp,   "<"],
  [:TkPLUS,       TkOp,   "+"],
  [:TkMINUS,      TkOp,   "-"],
  [:TkMULT,       TkOp,   "*"],
  [:TkDIV,        TkOp,   "/"],
  [:TkMOD,        TkOp,   "%"],
  [:TkBITOR,      TkOp,   "|"],
  [:TkBITXOR,     TkOp,   "^"],
  [:TkBITAND,     TkOp,   "&"],
  [:TkBITNOT,     TkOp,   "~"],
  [:TkNOTOP,      TkOp,   "!"],

  [:TkBACKQUOTE,  TkOp,   "`"],

  [:TkASSIGN,     Token,  "="],
  [:TkDOT,        Token,  "."],
  [:TkLPAREN,     Token,  "("],  #(exp)
  [:TkLBRACK,     Token,  "["],  #[arry]
  [:TkLBRACE,     Token,  "{"],  #{hash}
  [:TkRPAREN,     Token,  ")"],
  [:TkRBRACK,     Token,  "]"],
  [:TkRBRACE,     Token,  "}"],
  [:TkCOMMA,      Token,  ","],
  [:TkSEMICOLON,  Token,  ";"],

  [:TkRD_COMMENT],
  [:TkSPACE],
  [:TkNL],
  [:TkEND_OF_SCRIPT],

  [:TkBACKSLASH,  TkUnknownChar,  "\\"],
  [:TkAT,         TkUnknownChar,  "@"],
  [:TkDOLLAR,     TkUnknownChar,  "\$"], #"
]