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

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

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

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

  [: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 #
  [:TkSYMBEG],          # :SYMBOL

  [: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,  ";"],

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

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