--
-- This is file `piton.lua',
-- generated with the docstrip utility.
--
-- The original source files were:
--
-- piton.dtx  (with options: `LUA')
-- ---------------------------------------------
-- Copyright (C) 2022-2025 by F. Pantigny
-- 
-- This file may be distributed and/or modified under the
-- conditions of the LaTeX Project Public License, either
-- version 1.3 of this license or (at your option) any later
-- version.  The latest version of this license is in:
-- 
--      http://www.latex-project.org/lppl.txt
-- 
-- and version 1.3 or later is part of all distributions of
-- LaTeX version 2005/12/01 or later.
-- -------------------------------------------
-- 
-- This file is part of the LuaLaTeX package 'piton'.
piton_version = "4.2c" -- 2025/03/04





piton.comment_latex = piton.comment_latex or ">"
piton.comment_latex = "#" .. piton.comment_latex
local sprintL3
function sprintL3 ( s )
  tex.sprint ( luatexbase.catcodetables.expl , s )
end
local P, S, V, C, Ct, Cc = lpeg.P, lpeg.S, lpeg.V, lpeg.C, lpeg.Ct, lpeg.Cc
local Cs , Cg , Cmt , Cb = lpeg.Cs, lpeg.Cg , lpeg.Cmt , lpeg.Cb
local B , R = lpeg.B , lpeg.R
local Q
function Q ( pattern )
  return Ct ( Cc ( luatexbase.catcodetables.CatcodeTableOther ) * C ( pattern ) )
end
local L
function L ( pattern ) return
  Ct ( C ( pattern ) )
end
local Lc
function Lc ( string ) return
  Cc ( { luatexbase.catcodetables.expl , string } )
end
local K
function K ( style , pattern ) return
  Lc ( [[ {\PitonStyle{ ]] .. style .. "}{" )
  * Q ( pattern )
  * Lc "}}"
end
local WithStyle
function WithStyle ( style , pattern ) return
    Ct ( Cc "Open" * Cc ( [[{\PitonStyle{]] .. style .. "}{" ) * Cc "}}" )
  * pattern
  * Ct ( Cc "Close" )
end
Escape = P ( false )
EscapeClean = P ( false )
if piton.begin_escape then
  Escape =
    P ( piton.begin_escape )
    * L ( ( 1 - P ( piton.end_escape ) ) ^ 1 )
    * P ( piton.end_escape )
  EscapeClean =
    P ( piton.begin_escape )
    * ( 1 - P ( piton.end_escape ) ) ^ 1
    * P ( piton.end_escape )
end
EscapeMath = P ( false )
if piton.begin_escape_math then
  EscapeMath =
    P ( piton.begin_escape_math )
    * Lc "$"
    * L ( ( 1 - P(piton.end_escape_math) ) ^ 1 )
    * Lc "$"
    * P ( piton.end_escape_math )
end
lpeg.locale(lpeg)
local alpha , digit = lpeg.alpha , lpeg.digit
local space = P " "
local letter = alpha + "_" + "â" + "à" + "ç" + "é" + "è" + "ê" + "ë" + "ï" + "î"
                    + "ô" + "û" + "ü" + "Â" + "À" + "Ç" + "É" + "È" + "Ê" + "Ë"
                    + "Ï" + "Î" + "Ô" + "Û" + "Ü"

local alphanum = letter + digit
local identifier = letter * alphanum ^ 0
local Identifier = K ( 'Identifier.Internal' , identifier )
local Number =
  K ( 'Number.Internal' ,
      ( digit ^ 1 * P "." * # ( 1 - P "." ) * digit ^ 0
        + digit ^ 0 * P "." * digit ^ 1
        + digit ^ 1 )
      * ( S "eE" * S "+-" ^ -1 * digit ^ 1 ) ^ -1
      + digit ^ 1
    )
local lpeg_central = 1 - S " '\"\r[({})]" - digit
if piton.begin_escape then
  lpeg_central = lpeg_central - piton.begin_escape
end
if piton.begin_escape_math then
  lpeg_central = lpeg_central - piton.begin_escape_math
end
local Word = Q ( lpeg_central ^ 1 )
local Space = Q " " ^ 1

local SkipSpace = Q " " ^ 0

local Punct = Q ( S ".,:;!" )

local Tab = "\t" * Lc [[ \__piton_tab: ]]
local SpaceIndentation = Lc [[ \__piton_leading_space: ]] * Q " "
local Delim = Q ( S "[({})]" )
local SpaceInString = space * Lc [[ \l__piton_space_in_string_tl ]]
local LPEG0 = { }
local LPEG1 = { }
local LPEG2 = { }
local LPEG_cleaner = { }
local Compute_braces
function Compute_braces ( lpeg_string ) return
  P { "E" ,
       E =
           (
             "{" * V "E" * "}"
             +
             lpeg_string
             +
             ( 1 - S "{}" )
           ) ^ 0
    }
end
local Compute_DetectedCommands
function Compute_DetectedCommands ( lang , braces ) return
  Ct (
       Cc "Open"
        * C ( piton.DetectedCommands * space ^ 0 * P "{" )
        * Cc "}"
     )
   * ( braces
       / ( function ( s )
             if s ~= '' then return
               LPEG1[lang] : match ( s )
             end
           end )
     )
   * P "}"
   * Ct ( Cc "Close" )
end
local Compute_LPEG_cleaner
function Compute_LPEG_cleaner ( lang , braces ) return
  Ct ( ( piton.DetectedCommands * "{"
          * ( braces
              / ( function ( s )
                    if s ~= '' then return
                      LPEG_cleaner[lang] : match ( s )
                    end
                  end )
            )
          * "}"
         + EscapeClean
         +  C ( P ( 1 ) )
        ) ^ 0 ) / table.concat
end
local ParseAgain
function ParseAgain ( code )
  if code ~= '' then return
    LPEG1[piton.language] : match ( code )
  end
end
local Beamer = P ( false )
local BeamerBeginEnvironments = P ( true )
local BeamerEndEnvironments = P ( true )
piton.BeamerEnvironments = P ( false )
for _ , x  in ipairs ( piton.beamer_environments )  do
  piton.BeamerEnvironments = piton.BeamerEnvironments + x
end
BeamerBeginEnvironments =
    ( space ^ 0 *
      L
        (
          P [[\begin{]] * piton.BeamerEnvironments * "}"
          * ( "<" * ( 1 - P ">" ) ^ 0 * ">" ) ^ -1
        )
      * "\r"
    ) ^ 0
BeamerEndEnvironments =
    ( space ^ 0 *
      L ( P [[\end{]] * piton.BeamerEnvironments * "}" )
      * "\r"
    ) ^ 0
local Compute_Beamer
function Compute_Beamer ( lang , braces )
  local lpeg = L ( P [[\pause]] * ( "[" * ( 1 - P "]" ) ^ 0 * "]" ) ^ -1 )
  lpeg = lpeg +
      Ct ( Cc "Open"
            * C ( piton.BeamerCommands
                  * ( "<" * ( 1 - P ">" ) ^ 0 * ">" ) ^ -1
                  * P "{"
                )
            * Cc "}"
         )
       * ( braces /
           ( function ( s ) if s ~= '' then return LPEG1[lang] : match ( s ) end end ) )
       * "}"
       * Ct ( Cc "Close" )
  lpeg = lpeg +
    L ( P [[\alt]] * "<" * ( 1 - P ">" ) ^ 0 * ">{" )
     * ( braces /
         ( function ( s ) if s ~= '' then return LPEG1[lang] : match ( s ) end end ) )
     * L ( P "}{" )
     * ( braces /
         ( function ( s ) if s ~= '' then return LPEG1[lang] : match ( s ) end end ) )
     * L ( P "}" )
  lpeg = lpeg +
      L ( P [[\temporal]] * "<" * ( 1 - P ">" ) ^ 0 * ">{" )
      * ( braces
          / ( function ( s )
              if s ~= '' then return LPEG1[lang] : match ( s ) end end ) )
      * L ( P "}{" )
      * ( braces
          / ( function ( s )
              if s ~= '' then return LPEG1[lang] : match ( s ) end end ) )
      * L ( P "}{" )
      * ( braces
          / ( function ( s )
              if s ~= '' then return LPEG1[lang] : match ( s ) end end ) )
      * L ( P "}" )
  for _ , x in ipairs ( piton.beamer_environments ) do
    lpeg = lpeg +
          Ct ( Cc "Open"
               * C (
                      P ( [[\begin{]] .. x .. "}" )
                      * ( "<" * ( 1 - P ">") ^ 0 * ">" ) ^ -1
                    )
               * Cc ( [[\end{]] .. x ..  "}" )
              )
          * (
              ( ( 1 - P ( [[\end{]] .. x .. "}" ) ) ^ 0 )
                  / ( function ( s )
                        if s ~= '' then return
                          LPEG1[lang] : match ( s )
                        end
                      end )
            )
          * P ( [[\end{]] .. x .. "}" )
          * Ct ( Cc "Close" )
  end
  return lpeg
end
local CommentMath =
  P "$" * K ( 'Comment.Math' , ( 1 - S "$\r" ) ^ 1  ) * P "$" -- $
local PromptHastyDetection =
  ( # ( P ">>>" + "..." ) * Lc [[ \__piton_prompt: ]] ) ^ -1
local Prompt =
  K ( 'Prompt' , ( ( P ">>>" + "..." ) * P " " ^ -1 + P ( true ) ) ) ^ -1
local EOL =
  P "\r"
  *
  (
    space ^ 0 * -1
    +
    Ct (
         Cc "EOL"
         *
         Ct ( Lc [[ \__piton_end_line: ]]
              * BeamerEndEnvironments
              *
                (
                    -1
                  +
                    BeamerBeginEnvironments
                  * PromptHastyDetection
                  * Lc [[ \__piton_newline:\__piton_begin_line: ]]
                  * Prompt
                )
            )
       )
  )
  * ( SpaceIndentation ^ 0 * # ( 1 - S " \r" ) ) ^ -1
local CommentLaTeX =
  P ( piton.comment_latex )
  * Lc [[{\PitonStyle{Comment.LaTeX}{\ignorespaces]]
  * L ( ( 1 - P "\r" ) ^ 0 )
  * Lc "}}"
  * ( EOL + -1 )
do
  local Operator =
    K ( 'Operator' ,
        P "!=" + "<>" + "==" + "<<" + ">>" + "<=" + ">=" + ":=" + "//" + "**"
        + S "-~+/*%=<>&.@|" )

  local OperatorWord =
    K ( 'Operator.Word' , P "in" + "is" + "and" + "or" + "not" )
  local For = K ( 'Keyword' , P "for" )
              * Space
              * Identifier
              * Space
              * K ( 'Keyword' , P "in" )

  local Keyword =
    K ( 'Keyword' ,
        P  "assert" + "as" + "break" + "case" + "class" + "continue" + "def" +
        "del" + "elif" + "else" + "except" + "exec" + "finally" + "for" + "from" +
        "global" + "if" + "import" + "lambda" + "non local" + "pass" + "return" +
        "try" + "while" + "with" + "yield" + "yield from" )
    + K ( 'Keyword.Constant' , P "True" + "False" + "None" )

  local Builtin =
    K ( 'Name.Builtin' ,
        P "__import__" + "abs" + "all" + "any" + "bin" + "bool" + "bytearray" +
        "bytes" + "chr" + "classmethod" + "compile" + "complex" + "delattr" +
        "dict" + "dir" + "divmod" + "enumerate" + "eval" + "filter" + "float" +
        "format" + "frozenset" + "getattr" + "globals" + "hasattr" + "hash" +
        "hex" + "id" + "input" + "int" + "isinstance" + "issubclass" + "iter" +
        "len" + "list" + "locals" + "map" + "max" + "memoryview" + "min" + "next"
        + "object" + "oct" + "open" + "ord" + "pow" + "print" + "property" +
        "range" + "repr" + "reversed" + "round" + "set" + "setattr" + "slice" +
        "sorted" + "staticmethod" + "str" + "sum" + "super" + "tuple" + "type" +
        "vars" + "zip" )

  local Exception =
    K ( 'Exception' ,
        P "ArithmeticError" + "AssertionError" + "AttributeError" +
        "BaseException" + "BufferError" + "BytesWarning" + "DeprecationWarning" +
        "EOFError" + "EnvironmentError" + "Exception" + "FloatingPointError" +
        "FutureWarning" + "GeneratorExit" + "IOError" + "ImportError" +
        "ImportWarning" + "IndentationError" + "IndexError" + "KeyError" +
        "KeyboardInterrupt" + "LookupError" + "MemoryError" + "NameError" +
        "NotImplementedError" + "OSError" + "OverflowError" +
        "PendingDeprecationWarning" + "ReferenceError" + "ResourceWarning" +
        "RuntimeError" + "RuntimeWarning" + "StopIteration" + "SyntaxError" +
        "SyntaxWarning" + "SystemError" + "SystemExit" + "TabError" + "TypeError"
        + "UnboundLocalError" + "UnicodeDecodeError" + "UnicodeEncodeError" +
        "UnicodeError" + "UnicodeTranslateError" + "UnicodeWarning" +
        "UserWarning" + "ValueError" + "VMSError" + "Warning" + "WindowsError" +
        "ZeroDivisionError" + "BlockingIOError" + "ChildProcessError" +
        "ConnectionError" + "BrokenPipeError" + "ConnectionAbortedError" +
        "ConnectionRefusedError" + "ConnectionResetError" + "FileExistsError" +
        "FileNotFoundError" + "InterruptedError" + "IsADirectoryError" +
        "NotADirectoryError" + "PermissionError" + "ProcessLookupError" +
        "TimeoutError" + "StopAsyncIteration" + "ModuleNotFoundError" +
        "RecursionError" )

  local RaiseException = K ( 'Keyword' , P "raise" ) * SkipSpace * Exception * Q "("
  local Decorator = K ( 'Name.Decorator' , P "@" * letter ^ 1  )
  local DefClass =
    K ( 'Keyword' , "class" ) * Space * K ( 'Name.Class' , identifier )
  local ImportAs =
    K ( 'Keyword' , "import" )
     * Space
     * K ( 'Name.Namespace' , identifier * ( "." * identifier ) ^ 0 )
     * (
         ( Space * K ( 'Keyword' , "as" ) * Space
            * K ( 'Name.Namespace' , identifier ) )
         +
         ( SkipSpace * Q "," * SkipSpace
            * K ( 'Name.Namespace' , identifier ) ) ^ 0
       )
  local FromImport =
    K ( 'Keyword' , "from" )
      * Space * K ( 'Name.Namespace' , identifier )
      * Space * K ( 'Keyword' , "import" )
  local PercentInterpol =
    K ( 'String.Interpol' ,
        P "%"
        * ( "(" * alphanum ^ 1 * ")" ) ^ -1
        * ( S "-#0 +" ) ^ 0
        * ( digit ^ 1 + "*" ) ^ -1
        * ( "." * ( digit ^ 1 + "*" ) ) ^ -1
        * ( S "HlL" ) ^ -1
        * S "sdfFeExXorgiGauc%"
      )
  local SingleShortString =
    WithStyle ( 'String.Short.Internal' ,
           Q ( P "f'" + "F'" )
           * (
               K ( 'String.Interpol' , "{" )
                * K ( 'Interpol.Inside' , ( 1 - S "}':" ) ^ 0  )
                * Q ( P ":" * ( 1 - S "}:'" ) ^ 0 ) ^ -1
                * K ( 'String.Interpol' , "}" )
               +
               SpaceInString
               +
               Q ( ( P "\\'" + "\\\\" + "{{" + "}}" + 1 - S " {}'" ) ^ 1 )
             ) ^ 0
           * Q "'"
         +
           Q ( P "'" + "r'" + "R'" )
           * ( Q ( ( P "\\'" + "\\\\" + 1 - S " '\r%" ) ^ 1 )
               + SpaceInString
               + PercentInterpol
               + Q "%"
             ) ^ 0
           * Q "'" )
  local DoubleShortString =
    WithStyle ( 'String.Short.Internal' ,
           Q ( P "f\"" + "F\"" )
           * (
               K ( 'String.Interpol' , "{" )
                 * K ( 'Interpol.Inside' , ( 1 - S "}\":" ) ^ 0 )
                 * ( K ( 'String.Interpol' , ":" ) * Q ( (1 - S "}:\"") ^ 0 ) ) ^ -1
                 * K ( 'String.Interpol' , "}" )
               +
               SpaceInString
               +
               Q ( ( P "\\\"" + "\\\\" + "{{" + "}}" + 1 - S " {}\"" ) ^ 1 )
              ) ^ 0
           * Q "\""
         +
           Q ( P "\"" + "r\"" + "R\"" )
           * ( Q ( ( P "\\\"" + "\\\\" + 1 - S " \"\r%" ) ^ 1 )
               + SpaceInString
               + PercentInterpol
               + Q "%"
             ) ^ 0
           * Q "\""  )

  local ShortString = SingleShortString + DoubleShortString
  local braces =
    Compute_braces
     (
         ( P "\"" + "r\"" + "R\"" + "f\"" + "F\"" )
             * ( P "\\\"" + 1 - S "\"" ) ^ 0 * "\""
       +
         ( P '\'' + 'r\'' + 'R\'' + 'f\'' + 'F\'' )
             * ( P '\\\'' + 1 - S '\'' ) ^ 0 * '\''
     )
  if piton.beamer then Beamer = Compute_Beamer ( 'python' , braces ) end
  DetectedCommands = Compute_DetectedCommands ( 'python' , braces )
  LPEG_cleaner.python = Compute_LPEG_cleaner ( 'python' , braces )
  local SingleLongString =
    WithStyle ( 'String.Long.Internal' ,
       ( Q ( S "fF" * P "'''" )
           * (
               K ( 'String.Interpol' , "{" )
                 * K ( 'Interpol.Inside' , ( 1 - S "}:\r" - "'''" ) ^ 0  )
                 * Q ( P ":" * (1 - S "}:\r" - "'''" ) ^ 0 ) ^ -1
                 * K ( 'String.Interpol' , "}"  )
               +
               Q ( ( 1 - P "'''" - S "{}'\r" ) ^ 1 )
               +
               EOL
             ) ^ 0
         +
           Q ( ( S "rR" ) ^ -1  * "'''" )
           * (
               Q ( ( 1 - P "'''" - S "\r%" ) ^ 1 )
               +
               PercentInterpol
               +
               P "%"
               +
               EOL
             ) ^ 0
        )
        * Q "'''"  )
  local DoubleLongString =
    WithStyle ( 'String.Long.Internal' ,
       (
          Q ( S "fF" * "\"\"\"" )
          * (
              K ( 'String.Interpol', "{"  )
                * K ( 'Interpol.Inside' , ( 1 - S "}:\r" - "\"\"\"" ) ^ 0 )
                * Q ( ":" * (1 - S "}:\r" - "\"\"\"" ) ^ 0 ) ^ -1
                * K ( 'String.Interpol' , "}"  )
              +
              Q ( ( 1 - S "{}\"\r" - "\"\"\"" ) ^ 1 )
              +
              EOL
            ) ^ 0
        +
          Q ( S "rR" ^ -1  * "\"\"\"" )
          * (
              Q ( ( 1 - P "\"\"\"" - S "%\r" ) ^ 1 )
              +
              PercentInterpol
              +
              P "%"
              +
              EOL
            ) ^ 0
       )
       * Q "\"\"\""
    )
  local LongString = SingleLongString + DoubleLongString
  local StringDoc =
      K ( 'String.Doc' , P "r" ^ -1 * "\"\"\"" )
        * ( K ( 'String.Doc' , (1 - P "\"\"\"" - "\r" ) ^ 0  ) * EOL
            * Tab ^ 0
          ) ^ 0
        * K ( 'String.Doc' , ( 1 - P "\"\"\"" - "\r" ) ^ 0 * "\"\"\"" )
  local Comment =
    WithStyle
     ( 'Comment' ,
       Q "#" * ( CommentMath + Q ( ( 1 - S "$\r" ) ^ 1 ) ) ^ 0  -- $
     )
    * ( EOL + -1 )
  local expression =
    P { "E" ,
         E = ( "'" * ( P "\\'" + 1 - S "'\r" ) ^ 0 * "'"
               + "\"" * ( P "\\\"" + 1 - S "\"\r" ) ^ 0 * "\""
               + "{" * V "F" * "}"
               + "(" * V "F" * ")"
               + "[" * V "F" * "]"
               + ( 1 - S "{}()[]\r," ) ) ^ 0 ,
         F = (   "{" * V "F" * "}"
               + "(" * V "F" * ")"
               + "[" * V "F" * "]"
               + ( 1 - S "{}()[]\r\"'" ) ) ^ 0
      }
  local Params =
    P { "E" ,
         E = ( V "F" * ( Q "," * V "F" ) ^ 0 ) ^ -1 ,
         F = SkipSpace * ( Identifier + Q "*args" + Q "**kwargs" ) * SkipSpace
             * (
                   K ( 'InitialValues' , "=" * expression )
                 + Q ":" * SkipSpace * K ( 'Name.Type' , identifier )
               ) ^ -1
      }
  local DefFunction =
    K ( 'Keyword' , "def" )
    * Space
    * K ( 'Name.Function.Internal' , identifier )
    * SkipSpace
    * Q "("  * Params * Q ")"
    * SkipSpace
    * ( Q "->" * SkipSpace * K ( 'Name.Type' , identifier ) ) ^ -1
    * ( C ( ( 1 - S ":\r" ) ^ 0 ) / ParseAgain )
    * Q ":"
    * ( SkipSpace
        * ( EOL + CommentLaTeX + Comment ) -- in all cases, that contains an EOL
        * Tab ^ 0
        * SkipSpace
        * StringDoc ^ 0 -- there may be additional docstrings
      ) ^ -1
  local ExceptionInConsole = Exception *  Q ( ( 1 - P "\r" ) ^ 0 ) * EOL
  local EndKeyword
    = Space + Punct + Delim + EOL + Beamer + DetectedCommands + Escape +
    EscapeMath + -1
  local Main =
       space ^ 0 * EOL -- faut-il le mettre en commentaire ?
       + Space
       + Tab
       + Escape + EscapeMath
       + CommentLaTeX
       + Beamer
       + DetectedCommands
       + LongString
       + Comment
       + ExceptionInConsole
       + Delim
       + Operator
       + OperatorWord * EndKeyword
       + ShortString
       + Punct
       + FromImport
       + RaiseException
       + DefFunction
       + DefClass
       + For
       + Keyword * EndKeyword
       + Decorator
       + Builtin * EndKeyword
       + Identifier
       + Number
       + Word
  LPEG1.python = Main ^ 0
  LPEG2.python =
    Ct (
         ( space ^ 0 * "\r" ) ^ -1
         * BeamerBeginEnvironments
         * PromptHastyDetection
         * Lc [[ \__piton_begin_line: ]]
         * Prompt
         * SpaceIndentation ^ 0
         * ( space ^ 1 * -1 + space ^ 0 * EOL + Main ) ^ 0
         * -1
         * Lc [[ \__piton_end_line: ]]
       )
end
do
  local SkipSpace = ( Q " " + EOL ) ^ 0
  local Space = ( Q " " + EOL ) ^ 1
  local braces = Compute_braces ( "\"" * ( 1 - S "\"" ) ^ 0 * "\"" )
  if piton.beamer then
    Beamer = Compute_Beamer ( 'ocaml' , braces )
  end
  DetectedCommands = Compute_DetectedCommands ( 'ocaml' , braces )
  local Q
  function Q ( pattern, strict )
    if strict ~= nil then
      return Ct ( Cc ( luatexbase.catcodetables.CatcodeTableOther ) * C ( pattern ) )
    else
      return Ct ( Cc ( luatexbase.catcodetables.CatcodeTableOther ) * C ( pattern ) )
          + Beamer + DetectedCommands + EscapeMath + Escape
    end
  end
  local K
  function K ( style , pattern, strict ) return
    Lc ( [[ {\PitonStyle{ ]] .. style .. "}{" )
    * Q ( pattern, strict )
    * Lc "}}"
  end
  local WithStyle
  function WithStyle ( style , pattern ) return
      Ct ( Cc "Open" * Cc ( [[{\PitonStyle{]] .. style .. "}{" ) * Cc "}}" )
    * (pattern + Beamer + DetectedCommands + EscapeMath + Escape)
    * Ct ( Cc "Close" )
  end
  local balanced_parens =
    P { "E" , E = ( "(" * V "E" * ")" + ( 1 - S "()" ) ) ^ 0 }
  local ocaml_string =
    P "\""
  * (
      P " "
      +
      P ( ( 1 - S " \"\r" ) ^ 1 )
      +
      EOL -- ?
    ) ^ 0
  * P "\""
  local String =
    WithStyle
      ( 'String.Long.Internal' ,
          Q "\""
        * (
            SpaceInString
            +
            Q ( ( 1 - S " \"\r" ) ^ 1 )
            +
            EOL
          ) ^ 0
        * Q "\""
      )
  local ext = ( R "az" + "_" ) ^ 0
  local open = "{" * Cg ( ext , 'init' ) * "|"
  local close = "|" * C ( ext ) * "}"
  local closeeq =
    Cmt ( close * Cb ( 'init' ) ,
          function ( s , i , a , b ) return a == b end )
  local QuotedStringBis =
    WithStyle ( 'String.Long.Internal' ,
        (
          Space
          +
          Q ( ( 1 - S " \r" ) ^ 1 )
          +
          EOL
        ) ^ 0  )
  local QuotedString =
    C ( open * ( 1 - closeeq ) ^ 0  * close ) /
    ( function ( s ) return QuotedStringBis : match ( s ) end )
  local comment =
      P {
          "A" ,
          A = Q "(*"
              * ( V "A"
                  + Q ( ( 1 - S "\r$\"" - "(*" - "*)" ) ^ 1 ) -- $
                  + ocaml_string
                  + "$" * K ( 'Comment.Math' , ( 1 - S "$\r" ) ^ 1 ) * "$" -- $
                  + EOL
                ) ^ 0
              * Q "*)"
        }
  local Comment = WithStyle ( 'Comment' , comment )
  local Delim = Q ( P "[|" + "|]" + S "[()]" )
  local Punct = Q ( S ",:;!" )
  local cap_identifier = R "AZ" * ( R "az" + R "AZ" + S "_'" + digit ) ^ 0
  local Constructor =
    K ( 'Name.Constructor' ,
        Q "`" ^ -1 * cap_identifier
        + Q "::"
        + Q ( "[" , true ) * SkipSpace * Q ( "]" , true) )
  local ModuleType = K ( 'Name.Type' , cap_identifier )
  local OperatorWord =
    K ( 'Operator.Word' ,
        P "asr" + "land" + "lor" + "lsl" + "lxor" + "mod" + "or" + "not" )
  local governing_keyword = P "and" + "begin" + "class" + "constraint" +
        "end" + "external" + "functor" + "include" + "inherit" + "initializer" +
        "in" + "let" + "method" + "module" + "object" + "open" + "rec" + "sig" +
        "struct" + "type" + "val"
  local Keyword =
    K ( 'Keyword' ,
        P "assert" + "as" + "done" + "downto" + "do" + "else" + "exception"
        + "for" + "function"  + "fun" + "if" + "lazy" + "match" + "mutable"
        + "new" + "of" + "private" + "raise" + "then" + "to" + "try"
        + "virtual" + "when" + "while" + "with" )
    + K ( 'Keyword.Constant' , P "true" + "false" )
    + K ( 'Keyword.Governing', governing_keyword )
  local EndKeyword
    = Space + Punct + Delim + EOL + Beamer + DetectedCommands + Escape
       + EscapeMath + -1
  local identifier = ( R "az" + "_" ) * ( R "az" + R "AZ" + S "_'" + digit ) ^ 0
                     - ( OperatorWord + Keyword ) * EndKeyword
  local Identifier = K ( 'Identifier.Internal' , identifier )
  local ocaml_char =
      P "'" *
      (
        ( 1 - S "'\\" )
        + "\\"
          * ( S "\\'ntbr \""
              + digit * digit * digit
              + P "x" * ( digit + R "af" + R "AF" )
                      * ( digit + R "af" + R "AF" )
                      * ( digit + R "af" + R "AF" )
              + P "o" * R "03" * R "07" * R "07" )
      )
      * "'"
  local Char =
    K ( 'String.Short.Internal', ocaml_char )
  local TypeParameter =
    K ( 'TypeParameter' ,
        "'" * Q"_" ^ -1 * alpha ^ 1 * ( # ( 1 - P "'" ) + -1 ) )
  local expression_for_fields_type =
    P { "E" ,
        E =  (  "{" * V "F" * "}"
              + "(" * V "F" * ")"
              + TypeParameter
              + ( 1 - S "{}()[]\r;" ) ) ^ 0 ,
        F = (    "{" * V "F" * "}"
              + "(" * V "F" * ")"
              + ( 1 - S "{}()[]\r\"'" ) + TypeParameter ) ^ 0
      }
  local expression_for_fields_value =
    P { "E" ,
        E =  (   "{" * V "F" * "}"
              + "(" * V "F" * ")"
              + "[" * V "F" * "]"
              + ocaml_string + ocaml_char
              + ( 1 - S "{}()[];" ) ) ^ 0 ,
        F = (    "{" * V "F" * "}"
              + "(" * V "F" * ")"
              + "[" * V "F" * "]"
              + ocaml_string + ocaml_char
              + ( 1 - S "{}()[]\"'" )) ^ 0
      }
  local OneFieldDefinition =
      ( K ( 'Keyword' , "mutable" ) * SkipSpace ) ^ -1
    * K ( 'Name.Field' , identifier ) * SkipSpace
    * Q ":" * SkipSpace
    * K ( 'TypeExpression' , expression_for_fields_type )
    * SkipSpace
  local OneField =
      K ( 'Name.Field' , identifier ) * SkipSpace
    * Q "=" * SkipSpace
    * ( C ( expression_for_fields_value ) / ParseAgain )
    * SkipSpace
  local RecordVal =
    Q "{" * SkipSpace
    *
      (
        OneField * ( Q ";" * SkipSpace * ( Comment * SkipSpace ) ^ 0 * OneField ) ^ 0
      )
    * SkipSpace
    * Q ";" ^ -1
    * SkipSpace
    * Comment ^ -1
    * SkipSpace
    * Q "}"
  local RecordType =
    Q "{" * SkipSpace
    *
      (
        OneFieldDefinition
        * ( Q ";" * SkipSpace * ( Comment * SkipSpace ) ^ 0 * OneFieldDefinition ) ^ 0
      )
    * SkipSpace
    * Q ";" ^ -1
    * SkipSpace
    * Comment ^ -1
    * SkipSpace
    * Q "}"
  local Record = RecordType + RecordVal
  local DotNotation =
    (
        K ( 'Name.Module' , cap_identifier )
          * Q "."
          * ( Identifier + Constructor + Q "(" + Q "[" + Q "{" ) ^ -1
        +
         Identifier
          * Q "."
          * K ( 'Name.Field' , identifier )
    )
    * ( Q "." * K ( 'Name.Field' , identifier ) ) ^ 0
  local Operator =
    K ( 'Operator' ,
        P "!=" + "<>" + "==" + "<<" + ">>" + "<=" + ">=" + ":=" + "||" + "&&" +
        "//" + "**" + ";;" + "->" + "+." + "-." + "*." + "/."
        + S "-~+/*%=<>&@|" )
  local Builtin =
    K ( 'Name.Builtin' , P "incr" + "decr" + "fst" + "snd" + "ref" )
  local Exception =
    K (   'Exception' ,
        P "Division_by_zero" + "End_of_File" + "Failure" + "Invalid_argument" +
        "Match_failure" + "Not_found" + "Out_of_memory" + "Stack_overflow" +
        "Sys_blocked_io" + "Sys_error" + "Undefined_recursive_module" )
  LPEG_cleaner.ocaml = Compute_LPEG_cleaner ( 'ocaml' , braces )
  local pattern_part =
    ( P "(" * balanced_parens * ")" + ( 1 - S ":()" ) + P "::" ) ^ 0
  local Argument =
    (  Q "~" * Identifier * Q ":" * SkipSpace ) ^ -1
    *
    (
        K ( 'Identifier.Internal' , identifier )
      +
        Q "(" * SkipSpace
        * ( C ( pattern_part ) / ParseAgain )
        * SkipSpace
        * ( Q ":" * K ( 'TypeExpression' , balanced_parens ) * SkipSpace ) ^ -1
        * Q ")"
    )
  local DefFunction =
    K ( 'Keyword.Governing' , "let open" )
    * Space
    * K ( 'Name.Module' , cap_identifier )
    +
    K ( 'Keyword.Governing' , P "let rec" + "let" + "and" )
      * Space
      * K ( 'Name.Function.Internal' , identifier )
      * Space
      * (
          Q "=" * SkipSpace * K ( 'Keyword' , "function" , true )
          +
          Argument * ( SkipSpace * Argument ) ^ 0
          * (
              SkipSpace
              * Q ":"
              * K ( 'TypeExpression' , ( 1 - P "=" ) ^ 0 )
            ) ^ -1
        )
  local DefModule =
    K ( 'Keyword.Governing' , "module" ) * Space
    *
      (
            K ( 'Keyword.Governing' , "type" ) * Space
          * K ( 'Name.Type' , cap_identifier )
        +
          K ( 'Name.Module' , cap_identifier ) * SkipSpace
          *
            (
              Q "(" * SkipSpace
                * K ( 'Name.Module' , cap_identifier ) * SkipSpace
                * Q ":" * SkipSpace
                * K ( 'Name.Type' , cap_identifier ) * SkipSpace
                *
                  (
                    Q "," * SkipSpace
                      * K ( 'Name.Module' , cap_identifier ) * SkipSpace
                      * Q ":" * SkipSpace
                      * K ( 'Name.Type' , cap_identifier ) * SkipSpace
                  ) ^ 0
                * Q ")"
            ) ^ -1
          *
            (
              Q "=" * SkipSpace
              * K ( 'Name.Module' , cap_identifier )  * SkipSpace
              * Q "("
              * K ( 'Name.Module' , cap_identifier ) * SkipSpace
                *
                (
                  Q ","
                  *
                  K ( 'Name.Module' , cap_identifier ) * SkipSpace
                ) ^ 0
              * Q ")"
            ) ^ -1
      )
    +
    K ( 'Keyword.Governing' , P "include" + "open" )
    * Space
    * K ( 'Name.Module' , cap_identifier )
  local DefType =
    K ( 'Keyword.Governing' , "type" )
    * Space
    * K ( 'TypeExpression' , Q ( 1 - P "=" - P "+=" ) ^ 1 )
    * SkipSpace
    * ( Q "+=" + Q "=" )
    * SkipSpace
    * (
        RecordType
        +
        WithStyle
         (
           'TypeExpression' ,
           (
             (
               EOL
               + comment
               +  Q ( 1
                      - P ";;"
                      - ( ( Space + EOL ) * governing_keyword * EndKeyword )
                    )
             ) ^ 0
             *
             (
               # ( ( Space + EOL ) * governing_keyword * EndKeyword )
               + Q ";;"
               + -1
             )
           )
         )
      )
  local Main =
      space ^ 0 * EOL
      + Space
      + Tab
      + Escape + EscapeMath
      + Beamer
      + DetectedCommands
      + TypeParameter
      + String + QuotedString + Char
      + Comment
      + Operator
      + Q "~" * Identifier * ( Q ":" ) ^ -1
      + Q ":" * # (1 - P ":") * SkipSpace
          * K ( 'TypeExpression' , balanced_parens ) * SkipSpace * Q ")"
      + Exception
      + DefType
      + DefFunction
      + DefModule
      + Record
      + Keyword * EndKeyword
      + OperatorWord * EndKeyword
      + Builtin * EndKeyword
      + DotNotation
      + Constructor
      + Identifier
      + Punct
      + Delim
      + Number
      + Word
  LPEG1.ocaml = Main ^ 0
  LPEG2.ocaml =
    Ct (
        ( P ":" + Identifier * SkipSpace * Q ":" ) * # ( 1 - P ":" )
          * SkipSpace
          * K ( 'TypeExpression' , ( 1 - P "\r" ) ^ 0 )
        +
        ( space ^ 0 * "\r" ) ^ -1
        * BeamerBeginEnvironments
        * Lc [[ \__piton_begin_line: ]]
        * SpaceIndentation ^ 0
        * ( ( space * Lc [[ \__piton_trailing_space: ]] ) ^ 1 * -1
              + space ^ 0 * EOL
              + Main
          ) ^ 0
        * -1
        * Lc [[ \__piton_end_line: ]]
      )
end
do
  local Delim = Q ( S "{[()]}" )
  local Punct = Q ( S ",:;!" )
  local identifier = letter * alphanum ^ 0

  local Operator =
    K ( 'Operator' ,
        P "!=" + "==" + "<<" + ">>" + "<=" + ">=" + "||" + "&&"
          + S "-~+/*%=<>&.@|!" )

  local Keyword =
    K ( 'Keyword' ,
        P "alignas" + "asm" + "auto" + "break" + "case" + "catch" + "class" +
        "const" + "constexpr" + "continue" + "decltype" + "do" + "else" + "enum" +
        "extern" + "for" + "goto" + "if" + "nexcept" + "private" + "public" +
        "register" + "restricted" + "return" + "static" + "static_assert" +
        "struct" + "switch" + "thread_local" + "throw" + "try" + "typedef" +
        "union" + "using" + "virtual" + "volatile" + "while"
      )
    + K ( 'Keyword.Constant' , P "default" + "false" + "NULL" + "nullptr" + "true" )

  local Builtin =
    K ( 'Name.Builtin' ,
        P "alignof" + "malloc" + "printf" + "scanf" + "sizeof" )

  local Type =
    K ( 'Name.Type' ,
        P "bool" + "char" + "char16_t" + "char32_t" + "double" + "float" + "int" +
        "int8_t" + "int16_t" + "int32_t" + "int64_t" + "long" + "short" + "signed"
        + "unsigned" + "void" + "wchar_t" ) * Q "*" ^ 0

  local DefFunction =
    Type
    * Space
    * Q "*" ^ -1
    * K ( 'Name.Function.Internal' , identifier )
    * SkipSpace
    * # P "("
  local DefClass =
    K ( 'Keyword' , "class" ) * Space * K ( 'Name.Class' , identifier )
  String =
    WithStyle ( 'String.Long.Internal' ,
        Q "\""
        * ( SpaceInString
            + K ( 'String.Interpol' ,
                  "%" * ( S "difcspxXou" + "ld" + "li" + "hd" + "hi" )
                )
            + Q ( ( P "\\\"" + 1 - S " \"" ) ^ 1 )
          ) ^ 0
        * Q "\""
      )
  local braces = Compute_braces ( "\"" * ( 1 - S "\"" ) ^ 0 * "\"" )
  if piton.beamer then Beamer = Compute_Beamer ( 'c' , braces ) end
  DetectedCommands = Compute_DetectedCommands ( 'c' , braces )
  LPEG_cleaner.c = Compute_LPEG_cleaner ( 'c' , braces )
  local Preproc = K ( 'Preproc' , "#" * ( 1 - P "\r" ) ^ 0  ) * ( EOL + -1 )
  local Comment =
    WithStyle ( 'Comment' ,
       Q "//" * ( CommentMath + Q ( ( 1 - S "$\r" ) ^ 1 ) ) ^ 0 ) -- $
              * ( EOL + -1 )

  local LongComment =
    WithStyle ( 'Comment' ,
                 Q "/*"
                 * ( CommentMath + Q ( ( 1 - P "*/" - S "$\r" ) ^ 1 ) + EOL ) ^ 0
                 * Q "*/"
              ) -- $
  local EndKeyword
    = Space + Punct + Delim + EOL + Beamer + DetectedCommands + Escape +
    EscapeMath  + -1
  local Main =
       space ^ 0 * EOL
       + Space
       + Tab
       + Escape + EscapeMath
       + CommentLaTeX
       + Beamer
       + DetectedCommands
       + Preproc
       + Comment + LongComment
       + Delim
       + Operator
       + String
       + Punct
       + DefFunction
       + DefClass
       + Type * ( Q "*" ^ -1 + EndKeyword )
       + Keyword * EndKeyword
       + Builtin * EndKeyword
       + Identifier
       + Number
       + Word
  LPEG1.c = Main ^ 0
  LPEG2.c =
    Ct (
         ( space ^ 0 * P "\r" ) ^ -1
         * BeamerBeginEnvironments
         * Lc [[ \__piton_begin_line: ]]
         * SpaceIndentation ^ 0
         * ( space ^ 1 * -1 + space ^ 0 * EOL + Main ) ^ 0
         * -1
         * Lc [[ \__piton_end_line: ]]
       )
end
do
  local LuaKeyword
  function LuaKeyword ( name ) return
    Lc [[ {\PitonStyle{Keyword}{ ]]
    * Q ( Cmt (
                C ( letter * alphanum ^ 0 ) ,
                function ( s , i , a ) return string.upper ( a ) == name end
              )
        )
    * Lc "}}"
  end
  local identifier =
    letter * ( alphanum + "-" ) ^ 0
    + P '"' * ( ( 1 - P '"' ) ^ 1 ) * '"'
  local Operator =
    K ( 'Operator' , P "=" + "!=" + "<>" + ">=" + ">" + "<=" + "<"  + S "*+/" )
  local Set
  function Set ( list )
    local set = { }
    for _ , l in ipairs ( list ) do set[l] = true end
    return set
  end
  local set_keywords = Set
   {
     "ABORT", "ACTION", "ADD", "AFTER", "ALL", "ALTER", "ALWAYS", "ANALYZE",
     "AND", "AS", "ASC", "ATTACH", "AUTOINCREMENT", "BEFORE", "BEGIN", "BETWEEN",
     "BY", "CASCADE", "CASE", "CAST", "CHECK", "COLLATE", "COLUMN", "COMMIT",
     "CONFLICT", "CONSTRAINT", "CREATE", "CROSS", "CURRENT", "CURRENT_DATE",
     "CURRENT_TIME", "CURRENT_TIMESTAMP", "DATABASE", "DEFAULT", "DEFERRABLE",
     "DEFERRED", "DELETE", "DESC", "DETACH", "DISTINCT", "DO", "DROP", "EACH",
     "ELSE", "END", "ESCAPE", "EXCEPT", "EXCLUDE", "EXCLUSIVE", "EXISTS",
     "EXPLAIN", "FAIL", "FILTER", "FIRST", "FOLLOWING", "FOR", "FOREIGN", "FROM",
     "FULL", "GENERATED", "GLOB", "GROUP", "GROUPS", "HAVING", "IF", "IGNORE",
     "IMMEDIATE", "IN", "INDEX", "INDEXED", "INITIALLY", "INNER", "INSERT",
     "INSTEAD", "INTERSECT", "INTO", "IS", "ISNULL", "JOIN", "KEY", "LAST",
     "LEFT", "LIKE", "LIMIT", "MATCH", "MATERIALIZED", "NATURAL", "NO", "NOT",
     "NOTHING", "NOTNULL", "NULL", "NULLS", "OF", "OFFSET", "ON", "OR", "ORDER",
     "OTHERS", "OUTER", "OVER", "PARTITION", "PLAN", "PRAGMA", "PRECEDING",
     "PRIMARY", "QUERY", "RAISE", "RANGE", "RECURSIVE", "REFERENCES", "REGEXP",
     "REINDEX", "RELEASE", "RENAME", "REPLACE", "RESTRICT", "RETURNING", "RIGHT",
     "ROLLBACK", "ROW", "ROWS", "SAVEPOINT", "SELECT", "SET", "TABLE", "TEMP",
     "TEMPORARY", "THEN", "TIES", "TO", "TRANSACTION", "TRIGGER", "UNBOUNDED",
     "UNION", "UNIQUE", "UPDATE", "USING", "VACUUM", "VALUES", "VIEW", "VIRTUAL",
     "WHEN", "WHERE", "WINDOW", "WITH", "WITHOUT"
   }
  local set_builtins = Set
   {
     "AVG" , "COUNT" , "CHAR_LENGTH" , "CONCAT" , "CURDATE" , "CURRENT_DATE" ,
     "DATE_FORMAT" , "DAY" , "LOWER" , "LTRIM" , "MAX" , "MIN" , "MONTH" , "NOW" ,
     "RANK" , "ROUND" , "RTRIM" , "SUBSTRING" , "SUM" , "UPPER" , "YEAR"
   }
  local Identifier =
    C ( identifier ) /
    (
      function ( s )
          if set_keywords[string.upper(s)] then return
            { [[{\PitonStyle{Keyword}{]] } ,
            { luatexbase.catcodetables.other , s } ,
            { "}}" }
          else
            if set_builtins[string.upper(s)] then return
              { [[{\PitonStyle{Name.Builtin}{]] } ,
              { luatexbase.catcodetables.other , s } ,
              { "}}" }
            else return
              { [[{\PitonStyle{Name.Field}{]] } ,
              { luatexbase.catcodetables.other , s } ,
              { "}}" }
            end
          end
      end
    )
  local String = K ( 'String.Long.Internal' , "'" * ( 1 - P "'" ) ^ 1 * "'" )
  local braces = Compute_braces ( "'" * ( 1 - P "'" ) ^ 1 * "'" )
  if piton.beamer then Beamer = Compute_Beamer ( 'sql' , braces ) end
  DetectedCommands = Compute_DetectedCommands ( 'sql' , braces )
  LPEG_cleaner.sql = Compute_LPEG_cleaner ( 'sql' , braces )
  local Comment =
    WithStyle ( 'Comment' ,
       Q "--"   -- syntax of SQL92
       * ( CommentMath + Q ( ( 1 - S "$\r" ) ^ 1 ) ) ^ 0 ) -- $
    * ( EOL + -1 )

  local LongComment =
    WithStyle ( 'Comment' ,
                 Q "/*"
                 * ( CommentMath + Q ( ( 1 - P "*/" - S "$\r" ) ^ 1 ) + EOL ) ^ 0
                 * Q "*/"
              ) -- $
  local EndKeyword
    = Space + Punct + Delim + EOL + Beamer + DetectedCommands + Escape +
      EscapeMath + -1
  local TableField =
         K ( 'Name.Table' , identifier )
       * Q "."
       * ( DetectedCommands + ( K ( 'Name.Field' , identifier ) ) ^ 0 )

  local OneField =
    (
      Q ( "(" * ( 1 - P ")" ) ^ 0 * ")" )
      +
          K ( 'Name.Table' , identifier )
        * Q "."
        * K ( 'Name.Field' , identifier )
      +
      K ( 'Name.Field' , identifier )
    )
    * (
        Space * LuaKeyword "AS" * Space * K ( 'Name.Field' , identifier )
      ) ^ -1
    * ( Space * ( LuaKeyword "ASC" + LuaKeyword "DESC" ) ) ^ -1

  local OneTable =
       K ( 'Name.Table' , identifier )
     * (
         Space
         * LuaKeyword "AS"
         * Space
         * K ( 'Name.Table' , identifier )
       ) ^ -1

  local WeCatchTableNames =
       LuaKeyword "FROM"
     * ( Space + EOL )
     * OneTable * ( SkipSpace * Q "," * SkipSpace * OneTable ) ^ 0
    + (
        LuaKeyword "JOIN" + LuaKeyword "INTO" + LuaKeyword "UPDATE"
        + LuaKeyword "TABLE"
      )
      * ( Space + EOL ) * OneTable
  local EndKeyword
    = Space + Punct + Delim + EOL + Beamer
        + DetectedCommands + Escape + EscapeMath + -1
  local Main =
       space ^ 0 * EOL
       + Space
       + Tab
       + Escape + EscapeMath
       + CommentLaTeX
       + Beamer
       + DetectedCommands
       + Comment + LongComment
       + Delim
       + Operator
       + String
       + Punct
       + WeCatchTableNames
       + ( TableField + Identifier ) * ( Space + Operator + Punct + Delim + EOL + -1 )
       + Number
       + Word
  LPEG1.sql = Main ^ 0
  LPEG2.sql =
    Ct (
         ( space ^ 0 * "\r" ) ^ -1
         * BeamerBeginEnvironments
         * Lc [[ \__piton_begin_line: ]]
         * SpaceIndentation ^ 0
         * ( space ^ 1 * -1 + space ^ 0 * EOL + Main ) ^ 0
         * -1
         * Lc [[ \__piton_end_line: ]]
       )
end
do
  local Punct = Q ( S ",:;!\\" )

  local Comment =
    WithStyle ( 'Comment' ,
                Q "#"
                * ( CommentMath + Q ( ( 1 - S "$\r" ) ^ 1 ) ) ^ 0 -- $
              )
       * ( EOL + -1 )

  local String =
    WithStyle ( 'String.Short.Internal' ,
                Q "\""
                * ( SpaceInString
                    + Q ( ( P "\\\"" + 1 - S " \"" ) ^ 1 )
                  ) ^ 0
                * Q "\""
              )
  local braces = Compute_braces ( P "\"" * ( P "\\\"" + 1 - P "\"" ) ^ 1 * "\"" )

  if piton.beamer then Beamer = Compute_Beamer ( 'minimal' , braces ) end

  DetectedCommands = Compute_DetectedCommands ( 'minimal' , braces )

  LPEG_cleaner.minimal = Compute_LPEG_cleaner ( 'minimal' , braces )

  local identifier = letter * alphanum ^ 0

  local Identifier = K ( 'Identifier.Internal' , identifier )

  local Delim = Q ( S "{[()]}" )

  local Main =
       space ^ 0 * EOL
       + Space
       + Tab
       + Escape + EscapeMath
       + CommentLaTeX
       + Beamer
       + DetectedCommands
       + Comment
       + Delim
       + String
       + Punct
       + Identifier
       + Number
       + Word
  LPEG1.minimal = Main ^ 0

  LPEG2.minimal =
    Ct (
         ( space ^ 0 * "\r" ) ^ -1
         * BeamerBeginEnvironments
         * Lc [[ \__piton_begin_line: ]]
         * SpaceIndentation ^ 0
         * ( space ^ 1 * -1 + space ^ 0 * EOL + Main ) ^ 0
         * -1
         * Lc [[ \__piton_end_line: ]]
       )
end
do

  local braces =
      P { "E" ,
           E = ( "{" * V "E" * "}" + ( 1 - S "{}" ) ) ^ 0
        }

  if piton.beamer then Beamer = Compute_Beamer ( 'verbatim' , braces ) end

  DetectedCommands = Compute_DetectedCommands ( 'verbatim' , braces )

  LPEG_cleaner.verbatim = Compute_LPEG_cleaner ( 'verbatim' , braces )
  local lpeg_central = 1 - S " \\\r"
  if piton.begin_escape then
    lpeg_central = lpeg_central - piton.begin_escape
  end
  if piton.begin_escape_math then
    lpeg_central = lpeg_central - piton.begin_escape_math
  end
  local Word = Q ( lpeg_central ^ 1 )

  local Main =
       space ^ 0 * EOL
       + Space
       + Tab
       + Escape + EscapeMath
       + Beamer
       + DetectedCommands
       + Q [[\]]
       + Word
  LPEG1.verbatim = Main ^ 0

  LPEG2.verbatim =
    Ct (
         ( space ^ 0 * "\r" ) ^ -1
         * BeamerBeginEnvironments
         * Lc [[ \__piton_begin_line: ]]
         * SpaceIndentation ^ 0
         * ( space ^ 1 * -1 + space ^ 0 * EOL + Main ) ^ 0
         * -1
         * Lc [[ \__piton_end_line: ]]
       )
end
function piton.Parse ( language , code )
  piton.language = language
  local t = LPEG2[language] : match ( code )
  if t == nil then
    sprintL3 [[ \__piton_error_or_warning:n { SyntaxError } ]]
    return -- to exit in force the function
  end
  local left_stack = {}
  local right_stack = {}
  for _ , one_item in ipairs ( t ) do
    if one_item[1] == "EOL" then
      for _ , s in ipairs ( right_stack ) do
        tex.sprint ( s )
      end
      for _ , s in ipairs ( one_item[2] ) do
        tex.tprint ( s )
      end
      for _ , s in ipairs ( left_stack ) do
        tex.sprint ( s )
      end
    else
      if one_item[1] == "Open" then
        tex.sprint( one_item[2] )
        table.insert ( left_stack , one_item[2] )
        table.insert ( right_stack , one_item[3] )
      else
        if one_item[1] == "Close" then
          tex.sprint ( right_stack[#right_stack] )
          left_stack[#left_stack] = nil
          right_stack[#right_stack] = nil
        else
          tex.tprint ( one_item )
        end
      end
    end
  end
end

function piton.ParseFile
  ( lang , name , first_line , last_line , splittable , split )
  local s = ''
  local i = 0
  for line in io.lines ( name ) do
    i = i + 1
    if i >= first_line then
      s = s .. '\r' .. line
    end
    if i >= last_line then break end
  end
  if string.byte ( s , 1 ) == 13 then
    if string.byte ( s , 2 ) == 239 then
      if string.byte ( s , 3 ) == 187 then
        if string.byte ( s , 4 ) == 191 then
          s = string.sub ( s , 5 , -1 )
        end
      end
    end
  end
  if split == 1 then
    piton.RetrieveGobbleSplitParse ( lang , 0 , splittable , s )
  else
    piton.RetrieveGobbleParse ( lang , 0 , splittable , s )
  end
end
function piton.RetrieveGobbleParse ( lang , n , splittable , code )
  local s
  s = ( ( P " " ^ 0 * "\r" ) ^ -1 * C ( P ( 1 ) ^ 0 ) * -1 ) : match ( code )
  piton.GobbleParse ( lang , n , splittable , s )
end
function piton.ParseBis ( lang , code )
  local s = ( Cs ( ( P '##' / '#' + 1 ) ^ 0 ) ) : match ( code )
  return piton.Parse ( lang , s )
end
function piton.ParseTer ( lang , code )
  local s
  s = ( Cs ( ( P [[\__piton_breakable_space: ]] / ' ' + 1 ) ^ 0 ) )
      : match ( code )
  s = ( Cs ( ( P [[\__piton_leading_space: ]] / '' + 1 ) ^ 0 ) )
      : match ( s )
  return piton.Parse ( lang , s )
end
local AutoGobbleLPEG =
      (  (
           P " " ^ 0 * "\r"
           +
           Ct ( C " " ^ 0 ) / table.getn
           * ( 1 - P " " ) * ( 1 - P "\r" ) ^ 0 * "\r"
         ) ^ 0
         * ( Ct ( C " " ^ 0 ) / table.getn
              * ( 1 - P " " ) * ( 1 - P "\r" ) ^ 0 ) ^ -1
       ) / math.min
local TabsAutoGobbleLPEG =
       (
         (
           P "\t" ^ 0 * "\r"
           +
           Ct ( C "\t" ^ 0 ) / table.getn
           * ( 1 - P "\t" ) * ( 1 - P "\r" ) ^ 0 * "\r"
         ) ^ 0
         * ( Ct ( C "\t" ^ 0 ) / table.getn
             * ( 1 - P "\t" ) * ( 1 - P "\r" ) ^ 0 ) ^ -1
       ) / math.min
local EnvGobbleLPEG =
      ( ( 1 - P "\r" ) ^ 0 * "\r" ) ^ 0
    * Ct ( C " " ^ 0 * -1 ) / table.getn
local remove_before_cr
function remove_before_cr ( input_string )
  local match_result = ( P "\r" ) : match ( input_string )
  if match_result then return
    string.sub ( input_string , match_result )
  else return
    input_string
  end
end
local gobble
function gobble ( n , code )
  code = remove_before_cr ( code )
  if n == 0 then return
    code
  else
    if n == -1 then
      n = AutoGobbleLPEG : match ( code )
    else
      if n == -2 then
        n = EnvGobbleLPEG : match ( code )
      else
        if n == -3 then
          n = TabsAutoGobbleLPEG : match ( code )
        end
      end
    end
    if n == 0 then return
      code
    else return
      ( Ct (
             ( 1 - P "\r" ) ^ (-n) * C ( ( 1 - P "\r" ) ^ 0 )
               * ( C "\r" * ( 1 - P "\r" ) ^ (-n) * C ( ( 1 - P "\r" ) ^ 0 )
           ) ^ 0 )
        / table.concat
      ) : match ( code )
    end
  end
end
function piton.GobbleParse ( lang , n , splittable , code )
  piton.ComputeLinesStatus ( code , splittable )
  piton.last_code = gobble ( n , code )
  piton.last_language = lang
  piton.CountLines ( piton.last_code )
  sprintL3 [[ \bool_if:NT \g__piton_footnote_bool \savenotes ]]
  piton.Parse ( lang , piton.last_code )
  sprintL3 [[ \vspace{2.5pt} ]]
  sprintL3 [[ \bool_if:NT \g__piton_footnote_bool \endsavenotes ]]
  sprintL3 [[ \par ]]
  if piton.write and piton.write ~= '' then
    local file = io.open ( piton.write , piton.write_mode )
    if file then
      file : write ( piton.get_last_code ( ) )
      file : close ( )
    else
      sprintL3 [[ \__piton_error_or_warning:n { FileError } ]]
    end
  end
end
function piton.GobbleSplitParse ( lang , n , splittable , code )
  local chunks
  chunks =
     (
       Ct (
            (
              P " " ^ 0 * "\r"
              +
              C ( ( ( 1 - P "\r" ) ^ 1 * "\r" - ( P " " ^ 0 * "\r" ) ) ^ 1 )
            ) ^ 0
          )
     ) : match ( gobble ( n , code ) )
  sprintL3 [[ \begingroup ]]
  sprintL3
    (
      [[ \PitonOptions { split-on-empty-lines = false, gobble = 0, ]]
      .. "language = " .. lang .. ","
      .. "splittable = " .. splittable .. "}"
    )
  for k , v in pairs ( chunks ) do
    if k > 1 then
      sprintL3 [[ \l__piton_split_separation_tl ]]
    end
    tex.sprint
      (
        [[\begin{]] .. piton.env_used_by_split .. "}\r"
        .. v
        .. [[\end{]] .. piton.env_used_by_split .. "}"
      )
  end
  sprintL3 [[ \endgroup ]]
end
function piton.RetrieveGobbleSplitParse ( lang , n , splittable , code )
  local s
  s = ( ( P " " ^ 0 * "\r" ) ^ -1 * C ( P ( 1 ) ^ 0 ) * -1 ) : match ( code )
  piton.GobbleSplitParse ( lang , n , splittable , s )
end
piton.string_between_chunks =
 [[ \par \l__piton_split_separation_tl \mode_leave_vertical: ]]
 .. [[ \int_gzero:N \g__piton_line_int ]]
function piton.get_last_code ( )
  return LPEG_cleaner[piton.last_language] : match ( piton.last_code )
end
function piton.CountLines ( code )
  local count = 0
  count =
     ( Ct ( ( ( 1 - P "\r" ) ^ 0 * C "\r" ) ^ 0
            * ( ( 1 - P "\r" ) ^ 1 * Cc "\r" ) ^ -1
            * -1
          ) / table.getn
     ) : match ( code )
  sprintL3 ( string.format ( [[ \int_set:Nn  \l__piton_nb_lines_int { %i } ]] , count ) )
end
function piton.CountNonEmptyLines ( code )
  local count = 0
  count =
     ( Ct ( ( P " " ^ 0 * "\r"
              + ( 1 - P "\r" ) ^ 0 * C "\r" ) ^ 0
            * ( 1 - P "\r" ) ^ 0
            * -1
          ) / table.getn
     ) : match ( code )
  sprintL3
   ( string.format ( [[ \int_set:Nn  \l__piton_nb_non_empty_lines_int { %i } ]] , count ) )
end
function piton.CountLinesFile ( name )
  local count = 0
  for line in io.lines ( name ) do count = count + 1 end
  sprintL3
   ( string.format ( [[ \int_set:Nn \l__piton_nb_lines_int { %i } ]], count ) )
end
function piton.CountNonEmptyLinesFile ( name )
  local count = 0
  for line in io.lines ( name ) do
    if not ( ( P " " ^ 0 * -1 ) : match ( line ) ) then
       count = count + 1
    end
  end
  sprintL3
   ( string.format ( [[ \int_set:Nn \l__piton_nb_non_empty_lines_int { % i } ]] , count ) )
end
function piton.ComputeRange(marker_beginning,marker_end,file_name)
  local s = ( Cs ( ( P '##' / '#' + 1 ) ^ 0 ) ) : match ( marker_beginning )
  local t = ( Cs ( ( P '##' / '#' + 1 ) ^ 0 ) ) : match ( marker_end )
  local first_line = -1
  local count = 0
  local last_found = false
  for line in io.lines ( file_name ) do
    if first_line == -1 then
      if string.sub ( line , 1 , #s ) == s then
        first_line = count
      end
    else
      if string.sub ( line , 1 , #t ) == t then
        last_found = true
        break
      end
    end
    count = count + 1
  end
  if first_line == -1 then
    sprintL3 [[ \__piton_error_or_warning:n { begin~marker~not~found } ]]
  else
    if last_found == false then
      sprintL3 [[ \__piton_error_or_warning:n { end~marker~not~found } ]]
    end
  end
  sprintL3 (
      [[ \int_set:Nn \l__piton_first_line_int { ]] .. first_line .. ' + 2 }'
      .. [[ \int_set:Nn \l__piton_last_line_int { ]] .. count .. ' }' )
end
function piton.ComputeLinesStatus ( code , splittable )
  local lpeg_line_beamer
  if piton.beamer then
    lpeg_line_beamer =
       space ^ 0
        * P [[\begin{]] * piton.BeamerEnvironments * "}"
        * ( "<" * ( 1 - P ">" ) ^ 0 * ">" ) ^ -1
       +
       space ^ 0
        * P [[\end{]] * piton.BeamerEnvironments * "}"
  else
    lpeg_line_beamer = P ( false )
  end
  local lpeg_empty_lines =
    Ct (
         ( lpeg_line_beamer * "\r"
           +
           P " " ^ 0 * "\r" * Cc ( 0 )
           +
           ( 1 - P "\r" ) ^ 0 * "\r" * Cc ( 1 )
         ) ^ 0
         *
         ( lpeg_line_beamer + ( 1 - P "\r" ) ^ 1 * Cc ( 1 ) ) ^ -1
       )
    * -1
  local lpeg_all_lines =
    Ct (
         ( lpeg_line_beamer * "\r"
           +
           ( 1 - P "\r" ) ^ 0 * "\r" * Cc ( 1 )
         ) ^ 0
         *
         ( lpeg_line_beamer + ( 1 - P "\r" ) ^ 1 * Cc ( 1 ) ) ^ -1
       )
    * -1
  piton.empty_lines = lpeg_empty_lines : match ( code )
  local lines_status
  local s = splittable
  if splittable < 0 then s = - splittable end
  if splittable > 0 then
    lines_status = lpeg_all_lines : match ( code )
  else
    lines_status = lpeg_empty_lines : match ( code )
    for i , x in ipairs ( lines_status ) do
      if x == 0 then
        for j = 1 , s - 1 do
          if i + j > #lines_status then break end
          if lines_status[i+j] == 0 then break end
            lines_status[i+j] = 2
        end
        for j = 1 , s - 1 do
          if i - j == 1 then break end
          if lines_status[i-j-1] == 0 then break end
          lines_status[i-j-1] = 2
        end
      end
    end
  end
  for j = 1 , s - 1 do
    if j > #lines_status then break end
    if lines_status[j] == 0 then break end
    lines_status[j] = 2
  end
  for j = 1 , s - 1 do
    if #lines_status - j == 0 then break end
    if lines_status[#lines_status - j] == 0 then break end
    lines_status[#lines_status - j] = 2
  end
  piton.lines_status = lines_status
end
function piton.new_language ( lang , definition )
  lang = string.lower ( lang )
  local alpha , digit = lpeg.alpha , lpeg.digit
  local extra_letters = { "@" , "_" , "$" } -- $
  function add_to_letter ( c )
    if c ~= " " then table.insert ( extra_letters , c ) end
  end
  function add_to_digit ( c )
    if c ~= " " then digit = digit + c end
  end
  local other = S ":_@+-*/<>!?;.()[]~^=#&\"\'\\$" -- $
  local extra_others = { }
  function add_to_other ( c )
    if c ~= " " then
      extra_others[c] = true
      other = other + P ( c )
    end
  end
  local def_table
  if ( S ", " ^ 0 * -1 ) : match ( definition ) then
    def_table = {}
  else
    local strict_braces  =
      P { "E" ,
          E = ( "{" * V "F" * "}" + ( 1 - S ",{}" ) ) ^ 0  ,
          F = ( "{" * V "F" * "}" + ( 1 - S "{}" ) ) ^ 0
        }
    local cut_definition =
      P { "E" ,
          E = Ct ( V "F" * ( "," * V "F" ) ^ 0 ) ,
          F = Ct ( space ^ 0 * C ( alpha ^ 1 ) * space ^ 0
                  * ( "=" * space ^ 0 * C ( strict_braces ) ) ^ -1 )
        }
    def_table = cut_definition : match ( definition )
  end
  local tex_braced_arg = "{" * C ( ( 1 - P "}" ) ^ 0 ) * "}"
  local tex_arg = tex_braced_arg + C ( 1 )
  local tex_option_arg =  "[" * C ( ( 1 - P "]" ) ^ 0 ) * "]" + Cc ( nil )
  local args_for_tag
    =  tex_option_arg
       * space ^ 0
       * tex_arg
       * space ^ 0
       * tex_arg
  local args_for_morekeywords
    = "[" * C ( ( 1 - P "]" ) ^ 0 ) * "]"
       * space ^ 0
       * tex_option_arg
       * space ^ 0
       * tex_arg
       * space ^ 0
       * ( tex_braced_arg + Cc ( nil ) )
  local args_for_moredelims
    = ( C ( P "*" ^ -2 ) + Cc ( nil ) ) * space ^ 0
      * args_for_morekeywords
  local args_for_morecomment
    = "[" * C ( ( 1 - P "]" ) ^ 0 ) * "]"
       * space ^ 0
       * tex_option_arg
       * space ^ 0
       * C ( P ( 1 ) ^ 0 * -1 )
  local sensitive = true
  local style_tag , left_tag , right_tag
  for _ , x in ipairs ( def_table ) do
    if x[1] == "sensitive" then
      if x[2] == nil or ( P "true" ) : match ( x[2] ) then
        sensitive = true
      else
        if ( P "false" + P "f" ) : match ( x[2] ) then sensitive = false end
      end
    end
    if x[1] == "alsodigit" then x[2] : gsub ( "." , add_to_digit ) end
    if x[1] == "alsoletter" then x[2] : gsub ( "." , add_to_letter ) end
    if x[1] == "alsoother" then x[2] : gsub ( "." , add_to_other ) end
    if x[1] == "tag" then
      style_tag , left_tag , right_tag = args_for_tag : match ( x[2] )
      style_tag = style_tag or [[\PitonStyle{Tag}]]
    end
  end
  local Number =
    K ( 'Number.Internal' ,
        ( digit ^ 1 * "." * # ( 1 - P "." ) * digit ^ 0
          + digit ^ 0 * "." * digit ^ 1
          + digit ^ 1 )
        * ( S "eE" * S "+-" ^ -1 * digit ^ 1 ) ^ -1
        + digit ^ 1
      )
  local string_extra_letters = ""
  for _ , x in ipairs ( extra_letters ) do
    if not ( extra_others[x] ) then
     string_extra_letters = string_extra_letters .. x
    end
  end
  local letter = alpha + S ( string_extra_letters )
                  + P "â" + "à" + "ç" + "é" + "è" + "ê" + "ë" + "ï" + "î"
                    + "ô" + "û" + "ü" + "Â" + "À" + "Ç" + "É" + "È" + "Ê" + "Ë"
                    + "Ï" + "Î" + "Ô" + "Û" + "Ü"
  local alphanum = letter + digit
  local identifier = letter * alphanum ^ 0
  local Identifier = K ( 'Identifier.Internal' , identifier )
  local split_clist =
    P { "E" ,
         E = ( "[" * ( 1 - P "]" ) ^ 0 * "]" ) ^ -1
             * ( P "{" ) ^ 1
             * Ct ( V "F" * ( "," * V "F" ) ^ 0 )
             * ( P "}" ) ^ 1 * space ^ 0 ,
         F = space ^ 0 * C ( letter * alphanum ^ 0 + other ^ 1 ) * space ^ 0
      }
  local keyword_to_lpeg
  function keyword_to_lpeg ( name ) return
    Q ( Cmt (
              C ( identifier ) ,
              function ( s , i , a ) return
                string.upper ( a ) == string.upper ( name )
              end
            )
      )
  end
  local Keyword = P ( false )
  local PrefixedKeyword = P ( false )
  for _ , x in ipairs ( def_table )
  do if x[1] == "morekeywords"
        or x[1] == "otherkeywords"
        or x[1] == "moredirectives"
        or x[1] == "moretexcs"
     then
        local keywords = P ( false )
        local style = [[\PitonStyle{Keyword}]]
        if x[1] == "moredirectives" then style = [[\PitonStyle{Directive}]] end
        style =  tex_option_arg : match ( x[2] ) or style
        local n = tonumber ( style )
        if n then
          if n > 1 then style = [[\PitonStyle{Keyword]] .. style .. "}" end
        end
        for _ , word in ipairs ( split_clist : match ( x[2] ) ) do
          if x[1] == "moretexcs" then
            keywords = Q ( [[\]] .. word ) + keywords
          else
            if sensitive
            then keywords = Q ( word  ) + keywords
            else keywords = keyword_to_lpeg ( word ) + keywords
            end
          end
        end
        Keyword = Keyword +
           Lc ( "{" .. style .. "{" ) * keywords * Lc "}}"
     end
     if x[1] == "keywordsprefix" then
       local prefix = ( ( C ( 1 - P " " ) ^ 1 ) * P " " ^ 0 ) : match ( x[2] )
       PrefixedKeyword = PrefixedKeyword
          + K ( 'Keyword' , P ( prefix ) * ( letter ^ 1 + other ) )
     end
  end
  local long_string  = P ( false )
  local Long_string = P ( false )
  local LongString = P (false )
  local central_pattern = P ( false )
  for _ , x in ipairs ( def_table ) do
    if x[1] == "morestring" then
      arg1 , arg2 , arg3 , arg4 = args_for_morekeywords : match ( x[2] )
      arg2 = arg2 or [[\PitonStyle{String.Long}]]
      if arg1 ~= "s" then
        arg4 = arg3
      end
      central_pattern = 1 - S ( " \r" .. arg4 )
      if arg1 : match "b" then
        central_pattern = P ( [[\]] .. arg3 ) + central_pattern
      end
      if arg1 : match "d" or arg1 == "m" then
        central_pattern = P ( arg3 .. arg3 ) + central_pattern
      end
      if arg1 == "m"
      then prefix = B ( 1 - letter - ")" - "]" )
      else prefix = P ( true )
      end
     long_string = long_string +
         prefix
         * arg3
         * ( space + central_pattern ) ^ 0
         * arg4
     local pattern =
         prefix
         * Q ( arg3 )
         * ( SpaceInString + Q ( central_pattern ^ 1 ) + EOL ) ^ 0
         * Q ( arg4 )
      Long_string = Long_string + pattern
      LongString = LongString +
         Ct ( Cc "Open" * Cc ( "{" ..  arg2 .. "{" ) * Cc "}}" )
         * pattern
         * Ct ( Cc "Close" )
    end
  end
  local braces = Compute_braces ( long_string )
  if piton.beamer then Beamer = Compute_Beamer ( lang , braces ) end

  DetectedCommands = Compute_DetectedCommands ( lang , braces )

  LPEG_cleaner[lang] = Compute_LPEG_cleaner ( lang , braces )
  local CommentDelim = P ( false )

  for _ , x in ipairs ( def_table ) do
    if x[1] == "morecomment" then
      local arg1 , arg2 , other_args = args_for_morecomment : match ( x[2] )
      arg2 = arg2 or [[\PitonStyle{Comment}]]
      if arg1 : match "i" then arg2 = [[\PitonStyle{Discard}]] end
      if arg1 : match "l" then
        local arg3 = ( tex_braced_arg + C ( P ( 1 ) ^ 0 * -1 ) )
                     : match ( other_args )
        if arg3 == [[\#]] then arg3 = "#" end -- mandatory
        if arg3 == [[\%]] then arg3 = "%" end -- mandatory¨
        CommentDelim = CommentDelim +
            Ct ( Cc "Open"
                 * Cc ( "{" .. arg2 .. "{" ) * Cc "}}" )
                 * Q ( arg3 )
                 * ( CommentMath + Q ( ( 1 - S "$\r" ) ^ 1 ) ) ^ 0 -- $
            * Ct ( Cc "Close" )
            * ( EOL + -1 )
      else
        local arg3 , arg4 =
          ( tex_arg * space ^ 0 * tex_arg ) : match ( other_args )
        if arg1 : match "s" then
          CommentDelim = CommentDelim +
              Ct ( Cc "Open" * Cc ( "{" .. arg2 .. "{" ) * Cc "}}" )
              * Q ( arg3 )
              * (
                  CommentMath
                  + Q ( ( 1 - P ( arg4 ) - S "$\r" ) ^ 1 ) -- $
                  + EOL
                ) ^ 0
              * Q ( arg4 )
              * Ct ( Cc "Close" )
        end
        if arg1 : match "n" then
          CommentDelim = CommentDelim +
            Ct ( Cc "Open" * Cc ( "{" .. arg2 .. "{" ) * Cc "}}" )
             * P { "A" ,
                  A = Q ( arg3 )
                      * ( V "A"
                          + Q ( ( 1 - P ( arg3 ) - P ( arg4 )
                                  - S "\r$\"" ) ^ 1 ) -- $
                          + long_string
                          +   "$" -- $
                              * K ( 'Comment.Math' , ( 1 - S "$\r" ) ^ 1 ) --$
                              * "$" -- $
                          + EOL
                        ) ^ 0
                      * Q ( arg4 )
                 }
            * Ct ( Cc "Close" )
        end
      end
    end
    if x[1] == "moredelim" then
      local arg1 , arg2 , arg3 , arg4 , arg5
        = args_for_moredelims : match ( x[2] )
      local MyFun = Q
      if arg1 == "*" or arg1 == "**" then
        function MyFun ( x )
          if x ~= '' then return
            LPEG1[lang] : match ( x )
          end
        end
      end
      local left_delim
      if arg2 : match "i" then
        left_delim = P ( arg4 )
      else
        left_delim = Q ( arg4 )
      end
      if arg2 : match "l" then
        CommentDelim = CommentDelim +
            Ct ( Cc "Open" * Cc ( "{" .. arg3 .. "{" ) * Cc "}}" )
            * left_delim
            * ( MyFun ( ( 1 - P "\r" ) ^ 1 ) ) ^ 0
            * Ct ( Cc "Close" )
            * ( EOL + -1 )
      end
      if arg2 : match "s" then
        local right_delim
        if arg2 : match "i" then
          right_delim = P ( arg5 )
        else
          right_delim = Q ( arg5 )
        end
        CommentDelim = CommentDelim +
            Ct ( Cc "Open" * Cc ( "{" .. arg3 .. "{" ) * Cc "}}" )
            * left_delim
            * ( MyFun ( ( 1 - P ( arg5 ) - "\r" ) ^ 1 ) + EOL ) ^ 0
            * right_delim
            * Ct ( Cc "Close" )
      end
    end
  end

  local Delim = Q ( S "{[()]}" )
  local Punct = Q ( S "=,:;!\\'\"" )
  local Main =
       space ^ 0 * EOL
       + Space
       + Tab
       + Escape + EscapeMath
       + CommentLaTeX
       + Beamer
       + DetectedCommands
       + CommentDelim
       + LongString
       + Delim
       + PrefixedKeyword
       + Keyword * ( -1 + # ( 1 - alphanum ) )
       + Punct
       + K ( 'Identifier.Internal' , letter * alphanum ^ 0 )
       + Number
       + Word
  LPEG1[lang] = Main ^ 0
  LPEG2[lang] =
    Ct (
         ( space ^ 0 * P "\r" ) ^ -1
         * BeamerBeginEnvironments
         * Lc [[ \__piton_begin_line: ]]
         * SpaceIndentation ^ 0
         * ( space ^ 1 * -1 + space ^ 0 * EOL + Main ) ^ 0
         * -1
         * Lc [[ \__piton_end_line: ]]
       )
  if left_tag then
    local Tag = Ct ( Cc "Open" * Cc ( "{" .. style_tag .. "{" ) * Cc "}}" )
                * Q ( left_tag * other ^ 0 ) -- $
                * ( ( ( 1 - P ( right_tag ) ) ^ 0 )
                  / ( function ( x ) return LPEG0[lang] : match ( x ) end ) )
                * Q ( right_tag )
                * Ct ( Cc "Close" )
    MainWithoutTag
            = space ^ 1 * -1
            + space ^ 0 * EOL
            + Space
            + Tab
            + Escape + EscapeMath
            + CommentLaTeX
            + Beamer
            + DetectedCommands
            + CommentDelim
            + Delim
            + LongString
            + PrefixedKeyword
            + Keyword * ( -1 + # ( 1 - alphanum ) )
            + Punct
            + K ( 'Identifier.Internal' , letter * alphanum ^ 0 )
            + Number
            + Word
    LPEG0[lang] = MainWithoutTag ^ 0
    local LPEGaux = Tab + Escape + EscapeMath + CommentLaTeX
                    + Beamer + DetectedCommands + CommentDelim + Tag
    MainWithTag
            = space ^ 1 * -1
            + space ^ 0 * EOL
            + Space
            + LPEGaux
            + Q ( ( 1 - EOL - LPEGaux ) ^ 1 )
    LPEG1[lang] = MainWithTag ^ 0
    LPEG2[lang] =
      Ct (
           ( space ^ 0 * P "\r" ) ^ -1
           * BeamerBeginEnvironments
           * Lc [[ \__piton_begin_line: ]]
           * SpaceIndentation ^ 0
           * LPEG1[lang]
           * -1
           * Lc [[ \__piton_end_line: ]]
         )
  end
end

