piton (8oct22)

git-svn-id: svn://tug.org/texlive/trunk@64656 c570f23f-e606-0410-a88d-b1316a301751

2 files changed, 609 insertions, 614 deletions

diff --git a/Master/texmf-dist/tex/lualatex/piton/piton.lua b/Master/texmf-dist/tex/lualatex/piton/piton.lua
deleted file mode 100644
index 2860246c4c3..00000000000
--- a/Master/texmf-dist/tex/lualatex/piton/piton.lua
+++ /dev/null
@@ -1,493 +0,0 @@
--- -*- coding: utf-8 ; -*-
---
--- This is file 'piton.lua' which is a part of the Latex package 'piton'
--- Copyright (C) 2022 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 version 0.6a of the package 'piton'
-
-local P, S, V , C , Ct, Cc, Cf = lpeg.P, lpeg.S, lpeg.V, lpeg.C, lpeg.Ct, lpeg.Cc, lpeg.Cf
-
-
---[[ By convention, a capture which provides as value a table (and not a string), provides, in fact,
-a string (the first element of the table) which is a formatting LaTeX instruction (it will be
-thrown back to TeX with normal catcodes (ant not ``other'' catcode for everybody).]]
-
-local function L(string)
-  return lpeg.Cc ( { string } ) 
-end 
-
-local function K(pattern, style)
-  return 
-     L ( "{\\PitonStyle{" .. style .. "}{" )
-     * lpeg.C(pattern)
-     * L ( "}}" )
-end
-
-
---[[ The text in "escape" (between begin_escape and end_escape) is captured
-and put in a table (with only one component). Indeed, we have decided that a capture
-which is encapsulated in a table must be transmitted to TeX with the normal TeX catcodes.]]
-
-local Escape = P(begin_escape)
-               * Ct ( C ( ( 1 - P(end_escape) ) ^ 1 ) )
-	       * P(end_escape)
-
-local EOL = ( P "\r" ) * L ( "\\pitonEOL" )
-
-
-
-lpeg.locale(lpeg) -- mandatory
-
-local alpha , digit , space , punct = lpeg.alpha , lpeg.digit , lpeg.space , lpeg.punct
-
-local letter = alpha + S"âàçéèêëïîôûüÂÀÇÉÈÊËÏÎÔÛÜ_" 
-
-local alphanum = letter + digit
-
-local identifier = letter * alphanum ^ 0
-
-local Identifier = C ( identifier )
-
-local Space = C ( ( space - P "\r" ) ^ 1 )
-
-local SkipSpace = C ( ( space - P "\r" ) ^ 0 )
-
-local Punct = C ( punct )
-
-
-local Number =
-   K (
-       ( digit^1 * P "." * digit^0 + digit^0 * P "." * digit^1 + digit^1 )
-       * ( S "eE" * S "+-" ^ -1 * digit^1 ) ^ -1
-       + digit^1 
-       , 'Number' ) 
-
-local Word = C ( ( ( 1 - space ) - S "'\"\r[()]" - digit ) ^ 1 )
-
-local Delim = C ( S "[()]" )
-
-
-local Keyword = 
-   K ( P "assert" + P "break" + P "case" + P "continue" + P "del"
-       + P "elif" + P "else" + P "except" + P "exec" + P "finally" + P "for" + P "from" 
-       + P "global" + P "if" + P "import" + P "lambda" + P "non local"
-       + P "pass" + P "return" + P "try" + P "while"
-       + P "with" + P "yield" + P "yield from" ,
-   'Keyword' )
-   + K ( P "True" + P "False" + P "None" , 'Keyword.Constant' ) 
-
-
-local Builtin = 
-   K ( P "__import__" + P "abs" + P "all" + P "any" + P "bin" + P "bool" + P "bytearray"
-     + P "bytes" + P "chr" + P "classmethod" + P "compile" + P "complex" + P "delattr"
-     + P "dict" + P "dir" + P "divmod" + P "enumerate" + P "eval" + P "filter"
-     + P "float" + P "format" + P "frozenset" + P "getattr" + P "globals" + P "hasattr"
-     + P "hash" + P "hex" + P "id" + P "input" + P "int" + P "isinstance" + P "issubclass"
-     + P "iter" + P "len" + P "list" + P "locals" + P "map" + P "max" + P "memoryview" + P "min"
-     + P "next" + P "object" + P "oct" + P "open" + P "ord" + P "pow" + P "print" + P "property"
-     + P "range" + P "repr" + P "reversed" + P "round" + P "set" + P "setattr" + P "slice"
-     + P "sorted" + P "staticmethod" + P "str" + P "sum" + P "super" + P "tuple" + P "type"
-     + P "vars" + P "zip" ,
-   'Name.Builtin' )
-
-
-local Exception =
-   K ( "ArithmeticError" + P "AssertionError" + P "AttributeError"
-    + P "BaseException" + P "BufferError" + P "BytesWarning" + P "DeprecationWarning"
-    + P "EOFError" + P "EnvironmentError" + P "Exception" + P "FloatingPointError"
-    + P "FutureWarning" + P "GeneratorExit" + P "IOError" + P "ImportError"
-    + P "ImportWarning" + P "IndentationError" + P "IndexError" + P "KeyError"
-    + P "KeyboardInterrupt" + P "LookupError" + P "MemoryError" + P "NameError"
-    + P "NotImplementedError" + P "OSError" + P "OverflowError"
-    + P "PendingDeprecationWarning" + P "ReferenceError" + P "ResourceWarning"
-    + P "RuntimeError" + P "RuntimeWarning" + P "StopIteration"
-    + P "SyntaxError" + P "SyntaxWarning" + P "SystemError" + P "SystemExit"
-    + P "TabError" + P "TypeError" + P "UnboundLocalError" + P "UnicodeDecodeError"
-    + P "UnicodeEncodeError" + P "UnicodeError" + P "UnicodeTranslateError"
-    + P "UnicodeWarning" + P "UserWarning" + P "ValueError" + P "VMSError"
-    + P "Warning" + P "WindowsError" + P "ZeroDivisionError"
-    + P "BlockingIOError" + P "ChildProcessError" + P "ConnectionError"
-    + P "BrokenPipeError" + P "ConnectionAbortedError" + P "ConnectionRefusedError"
-    + P "ConnectionResetError" + P "FileExistsError" + P "FileNotFoundError"
-    + P "InterruptedError" + P "IsADirectoryError" + P "NotADirectoryError"
-    + P "PermissionError" + P "ProcessLookupError" + P "TimeoutError"
-    + P "StopAsyncIteration" + P "ModuleNotFoundError" + P "RecursionError" ,
-   'Exception' )
-
-local RaiseException = K ( P "raise" , 'Keyword' ) * SkipSpace * Exception * C ( P "(" ) 
-
-local ExceptionInConsole = Exception *  C ( ( 1 - P "\r" ) ^ 0 ) * EOL  
-
-
-local Namespace =
-   K ( P "from" , 'Keyword' ) * Space * K ( alphanum^1 , 'Name.Namespace' )
-   *  ( Space * K ( P "import" , 'Keyword' ) ) ^ -1
-
-
-local ImportAs = K ( P "import" , 'Keyword' )
-                  * Space
-		  * K ( identifier , 'Name.Namespace' )
-		  * ( SkipSpace * C ( P "," ) * SkipSpace * K ( identifier , 'Name.Namespace' ) ) ^ 0 
-		  * (
-		      Space * K ( P "as" , 'Keyword' ) * Space * K ( identifier , 'Name.Namespace' )
-		    ) ^ 0 
-
-local Class = K ( P "class" , 'Keyword' ) * Space * K ( identifier , 'Name.Class' )
-
-local Decorator = K ( P "@" * letter^1 , 'Name.Decorator' ) 
-
-local SingleShortInterpol =
-    K ( P "{" , 'String.Interpol')
-  * K ( ( 1 - S "}':" ) ^ 0 , 'Interpol.Inside' )
-  * C ( P ":" * (1 - S "}:'") ^ 0 ) ^ -1
-  * K ( P "}" , 'String.Interpol' )
-
-local DoubleShortInterpol =
-    K ( P "{" , 'String.Interpol' )
-  * K ( ( 1 - S "}\":" ) ^ 0 , 'Interpol.Inside' )
-  * ( K ( P ":" , 'String.Interpol' ) * C ( (1 - S "}:\"") ^ 0 ) ) ^ -1
-  * K ( P "}" , 'String.Interpol' )
-
-local SingleLongInterpol =
-    K ( P "{" , 'String.Interpol' )
-  * K ( ( 1 - S "}:\r" - P "'''" ) ^ 0 , 'Interpol.Inside' )
-  * C ( P ":" * (1 - S "}:\r" - P "'''" ) ^ 0 ) ^ -1
-  * K ( P "}" , 'String.Interpol' )
-
-local DoubleLongInterpol =
-    K ( P "{" , 'String.Interpol' )
-  * K ( ( 1 - S "}:\r" - P "\"\"\"" ) ^ 0 , 'Interpol.Inside' )
-  * C ( P ":" * (1 - S "}:\r" - P "\"\"\"" ) ^ 0 ) ^ -1
-  * K ( P "}" , 'String.Interpol' )
-
-local SingleShortPureString = C ( ( P "\\'" + P "{{" + P "}}" + 1 - S "{}'" ) ^ 1 )
-
-local DoubleShortPureString = C ( ( P "\\\"" + P "{{" + P "}}" + 1 - S "{}\"" ) ^ 1 )
-
-local SingleLongPureString = C ( ( 1 - P "'''" - S "{}'\r" ) ^ 1 )
-
-local DoubleLongPureString = C ( ( 1 - P "\"\"\"" - S "{}\"\r" ) ^ 1 ) 
-
-local SingleShortString =
-    L ( "{\\PitonStyle{String.Short}{" )
-     * (
-           C ( P "f'" + P "F'" ) 
-           * ( SingleShortInterpol + SingleShortPureString ) ^ 0 
-           * C ( P "'" )
-         + 
-           C ( ( P "'" + P "r'" + P "R'" ) * ( P "\\'" + 1 - S "'\r" ) ^ 0 * P "'" )
-       )
-     * L ( "}}" ) 
-
-local DoubleShortString =
-    L ( "{\\PitonStyle{String.Short}{" )
-     * (
-           C ( P "f\"" + P "F\"" ) 
-           * ( DoubleShortInterpol + DoubleShortPureString ) ^ 0 
-           * C ( P "\"" )
-         +
-           C ( ( P "\"" + P "r\"" + P "R\"" ) * ( P "\\\"" + 1 - S "\"\r" ) ^ 0 * P "\"" )
-       )
-     * L ( "}}" ) 
-
-
-local ShortString = SingleShortString + DoubleShortString
-
-
-local SingleLongString =
-      L "{\\PitonStyle{String.Long}{" 
-       * (
-      	     C ( S "fF" * P "'''" )
-      	     * ( SingleLongInterpol + SingleLongPureString ) ^ 0
-	     * L "}}" 
-      	     * (
-	         EOL
-	         + 
-      	         L "{\\PitonStyle{String.Long}{" 
-      	         * ( SingleLongInterpol + SingleLongPureString ) ^ 0
-      	         * L "}}"
-      	         * EOL
-      	       ) ^ 0 
-      	     * L "{\\PitonStyle{String.Long}{" 
-      	     * ( SingleLongInterpol + SingleLongPureString ) ^ 0
-           +
-	     C ( ( S "rR" ) ^ -1  * P "'''" * ( 1 - P "'''" - P "\r" ) ^ 0 ) 
-      	     * L "}}" 
-      	     * (
-      	         L "{\\PitonStyle{String.Long}{" 
-      	         * C ( ( 1 - P "'''" - P "\r" ) ^ 0 )
-      	         * L "}}" 
-      	         * EOL
-      	       ) ^ 0 
-      	     * L "{\\PitonStyle{String.Long}{" 
-      	     * C ( ( 1 - P "'''" - P "\r" ) ^ 0 )
-          )
-       * C ( P "'''" )
-       * L "}}" 
-
-
-local DoubleLongString =
-      L "{\\PitonStyle{String.Long}{" 
-       * (
-      	     C ( S "fF" * P "\"\"\"" )
-      	     * ( DoubleLongInterpol + DoubleLongPureString ) ^ 0
-	     * L "}}" 
-      	     * (
-	         EOL
-	         + 
-      	         L "{\\PitonStyle{String.Long}{" 
-      	         * ( DoubleLongInterpol + DoubleLongPureString ) ^ 0
-      	         * L "}}" 
-      	         * EOL
-      	       ) ^ 0 
-      	     * L "{\\PitonStyle{String.Long}{" 
-      	     * ( DoubleLongInterpol + DoubleLongPureString ) ^ 0
-           +
-	     C ( ( S "rR" ) ^ -1  * P "\"\"\"" * ( 1 - P "\"\"\"" - P "\r" ) ^ 0 ) 
-      	     * L "}}" 
-      	     * (
-      	         L "{\\PitonStyle{String.Long}{" 
-      	         * C ( ( 1 - P "\"\"\"" - P "\r" ) ^ 0 )
-      	         * L "}}" 
-      	         * EOL
-      	       ) ^ 0 
-      	     * L "{\\PitonStyle{String.Long}{" 
-      	     * C ( ( 1 - P "\"\"\"" - P "\r" ) ^ 0 )
-          )
-       * C ( P "\"\"\"" )
-       * L "}}" 
-
-
-
-local LongString = SingleLongString + DoubleLongString
-
-
-local Expression =
-    P { "E" ,
-         E = ( 1 - S "{}()[]\r," ) ^ 0
-	     *  (
-	          (   P "{" * V "F" * P "}"
-	            + P "(" * V "F" * P ")"
-		    + P "[" * V "F" * P "]" ) * ( 1 - S "{}()[]\r," ) ^ 0
-		) ^ 0 ,
-	 F = ( 1 - S "{}()[]\r\"'" ) ^ 0
-	     * ( (
-	             P "'" * (P "\\'" + 1 - S"'\r" )^0 * P "'"
-                   + P "\"" * (P "\\\"" + 1 - S"\"\r" )^0 * P "\""
-	           + P "{"  * V "F" * P "}"
-		   + P "(" * V "F" * P ")"
-		   + P "[" * V "F" * P "]"
-	         ) * ( 1 - S "{}()[]\r\"'" ) ^ 0 ) ^ 0 , 
-      }
-
-local Param = SkipSpace * K ( identifier , '' ) * SkipSpace
-                     *  ( K ( P "=" * Expression , 'InitialValues' )
-		          +  K ( P ":" , '' ) * SkipSpace * K ( letter^1 , 'Name.Type' ))
-		  + SkipSpace * K ( alphanum ^ 1 , '' ) * SkipSpace 
-
-local Params =  Param * (  K ( P "," , '' ) * Param ) ^ 0
-
-local StringDoc = K ( P "\"\"\"" , 'String.Doc' )
-                      * ( K ( (1 - P "\"\"\"" - P "\r" ) ^ 0 , 'String.Doc' ) * EOL ) ^ 0
-                      * K ( ( 1 - P "\"\"\"" - P "\r" ) ^ 0 * P "\"\"\"" , 'String.Doc' )
-		  + K ( P "'''" , 'String.Doc' )
-                      * ( K ( (1 - P "'''" - P "\r")^0 , 'String.Doc' ) * EOL ) ^ 0
-                      * K ( ( 1 - P "'''" - P "\r")^0 * P "'''" , 'String.Doc' )
-
-local CommentMath = P "$" * K ( ( 1 - S "$\r" ) ^ 1 , 'Comment.Math' ) * P "$"
-
-
-local Comment = L ( "{\\pitonStyleComment {" ) 
-		* C ( P "#" ) * ( CommentMath + C ( ( 1 - S "$\r" ) ^ 1 ) ) ^ 0
-                * L ( "}}" )
-		* ( EOL + -1 )
-
-local CommentLaTeX =
-   P "##"
-   * L "{\\PitonStyle{Comment.LaTeX}{\\ignorespaces" 
-   * Ct ( C ( ( 1 - P "\r" ) ^ 0 ) ) 
-   * L "}}" 
-   * ( EOL + -1 ) 
-
-local DefFunction =
-   K ( P "def" , 'Keyword' )
-     * Space
-     * K ( identifier , 'Name.Function' ) 
-     * ( SkipSpace * K ( P "(" , '' ) * Params * K ( P ")" , '' ) ) ^ -1
-     * ( SkipSpace
-          * K ( ( 1 - S ":\r" )^0 , 'Post.Function' ) 
-          * K ( P ":" , 'Keyword' )
-          * SkipSpace
-	  * ( EOL + CommentLaTeX + Comment )
-          * SkipSpace
-	  * StringDoc ) ^ -1
-
-local ItemDict = ShortString * SkipSpace * C ( P ":" ) * K ( Expression , 'Dict.Value' ) 
-
-local ItemOfSet = SkipSpace * ( ItemDict + ShortString ) * SkipSpace 
-
-local Set = C ( P "{" ) 
-            * ItemOfSet * ( C ( P "," ) * ItemOfSet )  ^ 0 
-            * C ( P "}" )
-
-
-local Operator = K ( P "!=" + P "==" + P "<<" + P ">>" + S "-~+/*%=<>&.@|" , 'Operator')
-
-local OperatorWord = K ( P "in" + P "is" + P "and" + P "or" + P "not" , 'Operator.Word')
-
-local SyntaxPython =
-      ( ( space - P "\r" ) ^0 * P "\r" ) ^ -1 * 
-      (  ( space^1 * -1 ) 
-         + EOL
-	 + Space
-	 + Escape 
-	 + CommentLaTeX
-	 + LongString 
-	 + Comment
-         + ExceptionInConsole
-         + Set 
-	 + Delim
-	 + Class * ( Space + Punct + EOL )
-	 + Namespace * ( Space + Punct + EOL )
-         + ImportAs
-	 + RaiseException 
-         + Keyword * ( Space + Punct + EOL )
-         + DefFunction
-         + ShortString
-	 + Decorator * ( Space + Punct + EOL )
-	 + Operator
-	 + OperatorWord * ( Space + Punct + EOL ) 
-	 + Builtin * ( Space + Punct + EOL )
-	 + Identifier 
-	 + Number
-	 + Word
-      ) ^0 * -1 
-
-
-local MinimalSyntax =
-  P { "S" ;
-      S = K ( (1 - P "\r" ) ^ 0 , '') + EOL * S
-    }
-
-
---- with cctab, all characters including spaces have catcode 12
-local cctab = luatexbase.catcodetables.CatcodeTableOther
-
-function Parse(code)
-  local t = Ct(SyntaxPython) : match(code)
-  if t then else t = Ct(MinimalSyntax) : match(code) end   
-  for i = 1 , #t do
-    if type(t[i]) == 'string'
-    then
-      tex.sprint(cctab, t[i])
-    else
-      tex.sprint( t[i][1] )
-    end 
-  end
-end
-
-
-
-
-function ParseFile(name)
-  s = ''
-  for line in io.lines(name) do s = s .. '\r' .. line end
-  Parse(s) 
-end
-
-
-function define_gobble_syntax(n) 
-  GobbleSyntax = ( 1 - P "\r" ) ^ (-n)  * C ( ( 1 - P "\r" ) ^0 ) 
-               * ( C ( P "\r" )
-	           * ( 1 - P "\r" ) ^ (-n)
-		   * C ( ( 1 - P "\r" ) ^0 )
-		 ) ^ 0
-end 
-
-function GobbleParse(code)
-  local t = Ct(GobbleSyntax):match(code)
-  local new_code = ""
-  for i = 1 , #t do
-    new_code = new_code .. t[i]
-  end
-  Parse(new_code)
-end
-
-
-function min(x,y)
-  if x <= y
-  then return x
-  else return y
-  end
-end
-
-function add(acc,new_value)
-  return acc + new_value
-end 
-
-
---[[ The following LPEG returns as capture the minimal number of spaces at
-the beginning of the lines of code]]
-AutoGobbleSyntax = 
-    ( space ^ 0 * P "\r" ) ^ -1 
-    * Cf (
-           (
-	     ( P " " ) ^ 0 * P "\r"
-	     + 
-	     Cf ( Cc(0) * ( P " " * Cc(1) ) ^ 0 , add )
-             * ( 1 - P " " ) * ( 1 - P "\r" ) ^ 0 * P "\r"
-	   ) ^ 0
-           *
-           ( Cf ( Cc(0) * ( P " " * Cc(1) ) ^ 0 , add )
-           * ( 1 - P " " ) * ( 1 - P "\r" ) ^ 0 ) ^ -1 ,
-	   min
-         )
-
-function AutoGobbleParse(code)
-  local n = AutoGobbleSyntax:match(code)
-  if n==0
-  then Parse(code)
-  else define_gobble_syntax(n)
-       GobbleParse(code) 
-  end 
-end
-
-
---[[ The following LPEG returns as capture the number of spaces at the last line,
-that is to say begin the \end{Piton} ]]
-
-EnvGobbleSyntax =
-       ( ( 1 - P "\r" ) ^ 0 * P "\r" ) ^ 0 
-         * Cf ( Cc(0) * ( P " " * Cc(1) ) ^ 0 , add ) * -1
-
-function EnvGobbleParse(code)
-  local n = EnvGobbleSyntax:match(code)
-  if n==0
-  then Parse(code)
-  else define_gobble_syntax(n)
-       GobbleParse(code) 
-  end 
-end
-
-
-
-  
-
-
-
-
-
-
-
-
diff --git a/Master/texmf-dist/tex/lualatex/piton/piton.sty b/Master/texmf-dist/tex/lualatex/piton/piton.sty
index 3d128105017..537e0694a93 100644
--- a/Master/texmf-dist/tex/lualatex/piton/piton.sty
+++ b/Master/texmf-dist/tex/lualatex/piton/piton.sty
@@ -18,8 +18,8 @@
 %% and version 1.3 or later is part of all distributions of
 %% LaTeX version 2005/12/01 or later.
 %% 
-\def\myfileversion{0.6a}
-\def\myfiledate{2022/09/19}
+\def\myfileversion{0.7}
+\def\myfiledate{2022/10/08}
 
 
 \NeedsTeXFormat{LaTeX2e}
@@ -36,29 +36,30 @@
 \keys_define:nn { piton / package }
   {
     escape-inside .tl_set:N = \c__piton_escape_inside_tl ,
+    escape-inside .initial:n = ,
     unknown .code:n = \msg_error:nn { piton } { unknown~key~for~package }
   }
 \msg_new:nnn { piton } { unknown~key~for~package }
   {
-    Unknown~key\\
+    Unknown~key.\\
     You~have~used~the~key~'\l_keys_key_str'~but~the~only~key~available~here~
-    is~the~key~'escape-inside'.\\
+    is~the~key~'escape-inside'.~Other~keys~are~available~in~\token_to_str:N
+    \PitonOptions.\\
     That~key~will~be~ignored.
   }
-\tl_clear_new:N \c__piton_escape_inside_tl
 \ProcessKeysOptions { piton / package }
 \begingroup
 \cs_new_protected:Npn \__piton_set_escape_char:nn #1 #2
   {
-    \directlua { begin_escape = "#1" }
-    \directlua { end_escape = "#2" }
+    \lua_now:n { begin_escape = "#1" }
+    \lua_now:n { end_escape = "#2" }
   }
 \cs_generate_variant:Nn \__piton_set_escape_char:nn { x x }
 \__piton_set_escape_char:xx
   { \tl_head:V \c__piton_escape_inside_tl }
   { \tl_tail:V \c__piton_escape_inside_tl }
 \endgroup
-\AtBeginDocument
+\hook_gput_code:nnn { begindocument } { . }
   {
     \@ifpackageloaded { xcolor }
       { }
@@ -70,64 +71,50 @@
     The~package~'xcolor'~is~required~by~'piton'.\\
     This~error~is~fatal.
   }
-\msg_new:nnn { piton } { piton.lua~not~found }
-  {
-    The~file~'piton.lua'~can't~be~found.\\
-    The package~'piton'~won't be loaded.
-  }
-\file_if_exist:nF { piton.lua }
-  { \msg_critical:nn { piton } { piton.lua~not~found} }
-\lua_now:e { require("piton.lua") }
-\cs_new:Npn \pitonEOL
-  {
-    \par \leavevmode
-    \__piton_print_number:
-  }
-\cs_new_protected:Npn \__piton_print_number:
-  {
-    \bool_if:NT \l__piton_line_numbers_bool
-      { \__piton_actually_print_number: }
-  }
-\cs_new_protected:Npn \__piton_actually_print_number:
-  {
-    \bool_if:NF \l__piton_all_line_numbers_bool
-      { \peek_meaning:NF \pitonEOL }
-    \__piton_actually_print_number_i:
-  }
-\cs_new_protected:Npn \__piton_actually_print_number_i:
-  {
-    \int_incr:N \l__piton_lineno_int
-    \hbox_overlap_left:n
-      {
-        { \color{gray} \footnotesize \int_to_arabic:n \l__piton_lineno_int }
-        \quad
-      }
-  }
-\int_new:N \l__piton_lineno_int
+\bool_new:N \l__piton_splittable_bool
+\str_new:N \l__piton_background_color_str
 \int_new:N \l__piton_gobble_int
 \cs_new_protected:Npn \__piton_define_gobble_syntax:n #1
   { \lua_now:n { define_gobble_syntax(#1) } }
-\NewDocumentCommand { \piton } { v }
+\cs_set_protected:Npn \__piton_begin_line: #1 \__piton_end_line:
   {
-    \group_begin:
-    \ttfamily
-    \lua_now:e { Parse(token.scan_argument()) } { #1 }
-    \group_end:
-  }
-\NewDocumentCommand { \PitonInputFile } { m }
-  {
-    \group_begin:
-      \ttfamily
-      \bool_if:NT \l__piton_line_numbers_bool
-        {
-          \__piton_actually_print_number:
-          \vspace{-\baselineskip}
-        }
-      \lua_now:e { ParseFile(token.scan_argument()) } { #1 }
-    \group_end:
+    \str_if_empty:NTF \l__piton_background_color_str
+      { \hbox_set:Nn \l_tmpa_box }
+      { \hbox_set_to_wd:Nnn \l_tmpa_box \linewidth }
+      {
+        \bool_if:NT \l__piton_line_numbers_bool
+          {
+            \bool_if:NF \l__piton_all_line_numbers_bool
+              { \tl_if_empty:nF { #1 } }
+              \__piton_print_number:
+          }
+        \strut
+        \str_if_empty:NF \l__piton_background_color_str \space
+        #1 \hfill
+      }
+    \box_set_dp:Nn \l_tmpa_box { \box_dp:N \l_tmpa_box + 1 pt }
+    \box_set_ht:Nn \l_tmpa_box { \box_ht:N \l_tmpa_box + 1.5 pt }
+    \tl_if_empty:NTF \l__piton_background_color_str
+      { \box_use_drop:N \l_tmpa_box }
+      {
+        \vbox_top:n
+          {
+            \hbox_to_wd:nn \linewidth
+              {
+                \exp_args:NV \color \l__piton_background_color_str
+                \vrule height \box_ht:N \l_tmpa_box
+                       depth \box_dp:N \l_tmpa_box
+                       width \linewidth
+              }
+            \skip_vertical:n { - \box_ht_plus_dp:N \l_tmpa_box }
+            \box_use_drop:N \l_tmpa_box
+          }
+      }
+    \vspace { - 2.5 pt }
   }
 \bool_new:N \l__piton_line_numbers_bool
 \bool_new:N \l__piton_all_line_numbers_bool
+\bool_new:N \l__piton_resume_bool
 \keys_define:nn { PitonOptions }
   {
     gobble           .int_set:N         = \l__piton_gobble_int ,
@@ -142,19 +129,60 @@
       \bool_set_true:N \l__piton_line_numbers_bool
       \bool_set_true:N \l__piton_all_line_numbers_bool ,
     all-line-numbers .value_forbidden:n = true  ,
+    resume           .bool_set:N        = \l__piton_resume_bool ,
+    resume           .value_forbidden:n = true ,
+    splittable        .bool_set:N      = \l__piton_splittable_bool ,
+    splittable        .default:n       = true ,
+    background-color .str_set:N         = \l__piton_background_color_str ,
+    background-color .value_required:n  = true ,
     unknown          .code:n =
       \msg_error:nn { piton } { Unknown~key~for~PitonOptions }
   }
 \msg_new:nnn { piton } { Unknown~key~for~PitonOptions }
   {
-    Unknown~key \\
+    Unknown~key. \\
     The~key~'\l_keys_key_str'~is~unknown~for~\token_to_str:N \PitonOptions.~The~
-    available~keys~are:~all-line-numbers,~auto-gobble,~env-gobble,~gobble~and~
-    line-numbers.\\
+    available~keys~are:~all-line-numbers,~auto-gobble,~env-gobble,~gobble,~
+    line-numbers,~resume~and~splittable.\\
     If~you~go~on,~that~key~will~be~ignored.
   }
-\NewDocumentCommand \PitonOptions { }
-  { \keys_set:nn { PitonOptions } }
+\NewDocumentCommand \PitonOptions { } { \keys_set:nn { PitonOptions } }
+\int_new:N \g__piton_line_int
+\cs_new_protected:Npn \__piton_print_number:
+  {
+    \int_gincr:N \g__piton_line_int
+    \hbox_overlap_left:n
+      {
+        { \color { gray } \footnotesize \int_to_arabic:n \g__piton_line_int }
+        \quad
+      }
+  }
+\NewDocumentCommand { \piton } { v }
+  {
+    \group_begin:
+      \ttfamily
+      \cs_set_protected:Npn \__piton_begin_line: { }
+      \cs_set_protected:Npn \__piton_end_line: { }
+      \lua_now:n { Parse(token.scan_argument()) } { #1 }
+    \group_end:
+  }
+\cs_new_protected:Npn \__piton_piton:n #1
+  {
+    \group_begin:
+      \cs_set_protected:Npn \__piton_begin_line: { }
+      \cs_set_protected:Npn \__piton_end_line: { }
+      \lua_now:e { Parse(token.scan_argument()) } { #1 }
+    \group_end:
+  }
+\NewDocumentCommand { \PitonInputFile } { m }
+  {
+    \bool_if:NF \l__piton_resume_bool { \int_gzero:N \g__piton_line_int }
+    \group_begin:
+      \dim_set_eq:NN \parindent \c_zero_dim
+      \ttfamily
+      \lua_now:e { ParseFile(token.scan_argument()) } { #1 }
+    \group_end:
+  }
 \NewDocumentCommand { \NewPitonEnvironment } { m m m m }
   {
     \use:x
@@ -166,37 +194,35 @@
       }
           {
             \group_end:
-            \par \addvspace { 0.5 em }
-            {
-              \dim_set_eq:NN \parindent \c_zero_dim
-              \ttfamily
-              \bool_if:NT \l__piton_line_numbers_bool
-                {
-                  \__piton_actually_print_number:
-                  \vspace{-\baselineskip}
-                }
-              \int_case:nnF \l__piton_gobble_int
-                {
-                  0
-                  { \lua_now:e { Parse(token.scan_argument()) } }
-                  { -1 }
-                  { \lua_now:e { AutoGobbleParse(token.scan_argument()) } }
-                  { -2 }
-                  { \lua_now:e { EnvGobbleParse(token.scan_argument()) } }
-                }
-                {
-                   \exp_args:NV \__piton_define_gobble_syntax:n \l__piton_gobble_int
-                   \lua_now:e { GobbleParse(token.scan_argument()) }
-                }
-              { ##1 }
-            }
-            \par \addvspace { 0.5 em }
+            \mode_if_vertical:TF \mode_leave_vertical: \newline
+            \bool_if:NF \l__piton_splittable_bool \vbox_top:n
+              {
+                \ttfamily
+                \dim_zero:N \lineskip
+                \int_case:nnF \l__piton_gobble_int
+                  {
+                    0
+                    { \lua_now:n { Parse(token.scan_argument()) } }
+                    { -1 }
+                    { \lua_now:n { AutoGobbleParse(token.scan_argument()) } }
+                    { -2 }
+                    { \lua_now:n { EnvGobbleParse(token.scan_argument()) } }
+                  }
+                  {
+                     \exp_args:NV \__piton_define_gobble_syntax:n \l__piton_gobble_int
+                     \lua_now:n { GobbleParse(token.scan_argument()) }
+                  }
+                { ##1 }
+                \vspace { 2.5 pt }
+              }
             \end { #1 }
           }
     \NewDocumentEnvironment { #1 } { #2 }
       {
         #3
+        \bool_if:NF \l__piton_resume_bool { \int_gzero:N \g__piton_line_int }
         \group_begin:
+        \box_clear:N \l_tmpa_box
         \tl_map_function:nN
           { \ \\ \{ \} \$ \& \# \^ \_ \% \~ }
           \char_set_catcode_other:N
@@ -206,11 +232,11 @@
     \AddToHook { env / #1 / begin } { \char_set_catcode_other:N \^^M }
   }
 \NewPitonEnvironment { Piton } { } { } { }
-\NewDocumentCommand { \PitonStyle } { m } { \csname pitonStyle#1\endcsname }
-\NewDocumentCommand { \SetPitonStyle } { } { \keys_set:nn { piton } }
+\NewDocumentCommand { \PitonStyle } { m } { \use:c { pitonStyle #1 } }
+\NewDocumentCommand { \SetPitonStyle } { } { \keys_set:nn { piton / Styles } }
 \cs_new_protected:Npn \__piton_math_scantokens:n #1
   { \normalfont \scantextokens { $#1$ } }
-\keys_define:nn { piton }
+\keys_define:nn { piton / Styles }
   {
     String.Interpol  .tl_set:c = pitonStyle String.Interpol ,
     String.Interpol  .value_required:n = true ,
@@ -262,32 +288,35 @@
     Exception        .value_required:n = true ,
     Comment.LaTeX    .tl_set:c = pitonStyle Comment.LaTeX ,
     Comment.LaTeX    .value_required:n = true ,
-    unknown          .code:n = \msg_error:nn { piton }{ Unknown~key~for~SetPitonStyle }
+    unknown          .code:n =
+      \msg_error:nn { piton } { Unknown~key~for~SetPitonStyle }
+  }
+\msg_new:nnn { piton } { Unknown~key~for~SetPitonStyle }
+  {
+    The~style~'\l_keys_key_str'~is~unknown.\\
+    This~key~will~be~ignored.\\
+    The~available~styles~are~(in~alphabetic~order):~
+    Comment,~
+    Comment.LaTeX,~
+    Dict.Value,~
+    Exception,~
+    InitialValues,~
+    Keyword,~
+    Keyword.Constant,~
+    Name.Builtin,~
+    Name.Class,~
+    Name.Decorator,~
+    Name.Function,~
+    Name.Namespace,~
+    Number,~
+    Operator,~
+    Operator.Word,~
+    String,~
+    String.Doc,~
+    String.Long,~
+    String.Short,~and~
+    String.Interpol.
   }
-\msg_new:nnn { piton } { Unknown~key~for~SetPitonStyle } {
-  The~style~'\l_keys_key_str'~is~unknown.\\
-  This~key~will~be~ignored.\\
-  The~available~styles~are~(in~alphabetic~order):~
-  Comment,~
-  Comment.LaTeX,~
-  Dict.Value,~
-  Exception,~
-  InitialValues,~
-  Keyword,~
-  Keyword.Constant,~
-  Name.Builtin,~
-  Name.Class,~
-  Name.Decorator,~
-  Name.Function,~
-  Name.Namespace,~
-  Number,~
-  Operator,~
-  Operator.Word,~
-  String,~
-  String.Doc,~
-  String.Long,~
-  String.Short,~and~
-  String.Interpol. }
 \SetPitonStyle
   {
     Comment          = \color[HTML]{0099FF} \itshape ,
@@ -307,11 +336,470 @@
     String.Interpol  = \color[HTML]{AA0000} ,
     Comment.LaTeX    = \normalfont \color[rgb]{.468,.532,.6} ,
     Name.Type        = \color[HTML]{336666} ,
-    InitialValues    = \piton ,
-    Dict.Value       = \piton ,
-    Post.Function    = \piton ,
-    Interpol.Inside  = \color{black}\piton ,
+    InitialValues    = \__piton_piton:n ,
+    Dict.Value       = \__piton_piton:n ,
+    Post.Function    = \__piton_piton:n ,
+    Interpol.Inside  = \color{black}\__piton_piton:n ,
+  }
+\AddToHook { env / piton / begin }
+   { \msg_fatal:nn { piton } { No~environment~piton } }
+
+\msg_new:nnn { piton } { No~environment~piton }
+  {
+    There~is~no~environment~piton!\\
+    There~is~an~environment~{Piton}~and~a~command~
+    \token_to_str:N \piton\ but~there~is~no~environment~
+    {piton}.~This~error~is~fatal.
   }
+\ExplSyntaxOff
+\RequirePackage{luacode}
+\begin{luacode*}
+local P, S, V , C , Ct, Cc, Cf = lpeg.P, lpeg.S, lpeg.V, lpeg.C, lpeg.Ct, lpeg.Cc, lpeg.Cf
+
+--[[ By convention, a capture which provides as value a table (and not a string), provides, in fact,
+a string (the first element of the table) which is a formatting LaTeX instruction (it will be
+thrown back to TeX with normal catcodes (ant not ``other'' catcode for everybody).]]
+
+local function L(string)
+  return Cc ( { string } )
+end
+
+local function K(pattern, style)
+  return
+     L ( "{\\PitonStyle{" .. style .. "}{" )
+     * C(pattern)
+     * L ( "}}" )
+end
+
+--[[ The text in "escape" (between begin_escape and end_escape) is captured
+and put in a table (with only one component). Indeed, we have decided that a capture
+which is encapsulated in a table must be transmitted to TeX with the normal TeX catcodes.]]
+
+local Escape = P(begin_escape)
+               * Ct ( C ( ( 1 - P(end_escape) ) ^ 1 ) )
+               * P(end_escape)
+
+lpeg.locale(lpeg) -- mandatory
+
+local alpha , digit , space , punct = lpeg.alpha , lpeg.digit , lpeg.space , lpeg.punct
+
+local letter = alpha + S"âàçéèêëïîôûüÂÀÇÉÈÊËÏÎÔÛÜ_"
+
+local alphanum = letter + digit
+
+local identifier = letter * alphanum ^ 0
+
+local Identifier = C ( identifier )
+
+local Space = C ( ( space - P "\r" ) ^ 1 )
+
+local SkipSpace = C ( ( space - P "\r" ) ^ 0 )
+
+local Punct = C ( punct )
+
+local EOL = ( P "\r" )
+            *
+            (
+              ( space^0 * -1 )
+              +
+              Cc (
+                   {
+                     luatexbase.catcodetables.expl ,
+                     '\\__piton_end_line: \\bool_if:NT \\l__piton_splittable_bool \\newline \\__piton_begin_line:'
+                   }
+                 )
+            )
+
+local Number =
+   K (
+       ( digit^1 * P "." * digit^0 + digit^0 * P "." * digit^1 + digit^1 )
+       * ( S "eE" * S "+-" ^ -1 * digit^1 ) ^ -1
+       + digit^1
+       , 'Number' )
+
+local Word = C ( ( ( 1 - space ) - S "'\"\r[()]" - digit ) ^ 1 )
+
+if begin_escape ~= ''
+then  Word = C ( ( ( 1 - space - P(begin_escape) - P(end_escape) ) - S "'\"\r[()]" - digit ) ^ 1 )
+end
+
+local Delim = C ( S "[()]" )
+
+local Keyword =
+   K ( P "assert" + P "break" + P "case" + P "continue" + P "del"
+       + P "elif" + P "else" + P "except" + P "exec" + P "finally" + P "for" + P "from"
+       + P "global" + P "if" + P "import" + P "lambda" + P "non local"
+       + P "pass" + P "return" + P "try" + P "while"
+       + P "with" + P "yield" + P "yield from" ,
+   'Keyword' )
+   + K ( P "True" + P "False" + P "None" , 'Keyword.Constant' )
+
+local Builtin =
+   K ( P "__import__" + P "abs" + P "all" + P "any" + P "bin" + P "bool" + P "bytearray"
+     + P "bytes" + P "chr" + P "classmethod" + P "compile" + P "complex" + P "delattr"
+     + P "dict" + P "dir" + P "divmod" + P "enumerate" + P "eval" + P "filter"
+     + P "float" + P "format" + P "frozenset" + P "getattr" + P "globals" + P "hasattr"
+     + P "hash" + P "hex" + P "id" + P "input" + P "int" + P "isinstance" + P "issubclass"
+     + P "iter" + P "len" + P "list" + P "locals" + P "map" + P "max" + P "memoryview" + P "min"
+     + P "next" + P "object" + P "oct" + P "open" + P "ord" + P "pow" + P "print" + P "property"
+     + P "range" + P "repr" + P "reversed" + P "round" + P "set" + P "setattr" + P "slice"
+     + P "sorted" + P "staticmethod" + P "str" + P "sum" + P "super" + P "tuple" + P "type"
+     + P "vars" + P "zip" ,
+   'Name.Builtin' )
+
+local Exception =
+   K ( "ArithmeticError" + P "AssertionError" + P "AttributeError"
+    + P "BaseException" + P "BufferError" + P "BytesWarning" + P "DeprecationWarning"
+    + P "EOFError" + P "EnvironmentError" + P "Exception" + P "FloatingPointError"
+    + P "FutureWarning" + P "GeneratorExit" + P "IOError" + P "ImportError"
+    + P "ImportWarning" + P "IndentationError" + P "IndexError" + P "KeyError"
+    + P "KeyboardInterrupt" + P "LookupError" + P "MemoryError" + P "NameError"
+    + P "NotImplementedError" + P "OSError" + P "OverflowError"
+    + P "PendingDeprecationWarning" + P "ReferenceError" + P "ResourceWarning"
+    + P "RuntimeError" + P "RuntimeWarning" + P "StopIteration"
+    + P "SyntaxError" + P "SyntaxWarning" + P "SystemError" + P "SystemExit"
+    + P "TabError" + P "TypeError" + P "UnboundLocalError" + P "UnicodeDecodeError"
+    + P "UnicodeEncodeError" + P "UnicodeError" + P "UnicodeTranslateError"
+    + P "UnicodeWarning" + P "UserWarning" + P "ValueError" + P "VMSError"
+    + P "Warning" + P "WindowsError" + P "ZeroDivisionError"
+    + P "BlockingIOError" + P "ChildProcessError" + P "ConnectionError"
+    + P "BrokenPipeError" + P "ConnectionAbortedError" + P "ConnectionRefusedError"
+    + P "ConnectionResetError" + P "FileExistsError" + P "FileNotFoundError"
+    + P "InterruptedError" + P "IsADirectoryError" + P "NotADirectoryError"
+    + P "PermissionError" + P "ProcessLookupError" + P "TimeoutError"
+    + P "StopAsyncIteration" + P "ModuleNotFoundError" + P "RecursionError" ,
+   'Exception' )
+
+local RaiseException = K ( P "raise" , 'Keyword' ) * SkipSpace * Exception * C ( P "(" )
+
+local ExceptionInConsole = Exception *  C ( ( 1 - P "\r" ) ^ 0 ) * EOL
+
+local Namespace =
+   K ( P "from" , 'Keyword' ) * Space * K ( alphanum^1 , 'Name.Namespace' )
+   *  ( Space * K ( P "import" , 'Keyword' ) ) ^ -1
+
+local ImportAs = K ( P "import" , 'Keyword' )
+                  * Space
+                  * K ( identifier , 'Name.Namespace' )
+                  * ( SkipSpace * C ( P "," ) * SkipSpace * K ( identifier , 'Name.Namespace' ) ) ^ 0
+                  * (
+                      Space * K ( P "as" , 'Keyword' ) * Space * K ( identifier , 'Name.Namespace' )
+                    ) ^ 0
+
+local Class = K ( P "class" , 'Keyword' )
+                * ( Space * K ( identifier , 'Name.Class' ) ) ^ -1
+
+local Decorator = K ( P "@" * letter^1 , 'Name.Decorator' )
+
+local SingleShortInterpol =
+    K ( P "{" , 'String.Interpol')
+  * K ( ( 1 - S "}':" ) ^ 0 , 'Interpol.Inside' )
+  * C ( P ":" * (1 - S "}:'") ^ 0 ) ^ -1
+  * K ( P "}" , 'String.Interpol' )
+
+local DoubleShortInterpol =
+    K ( P "{" , 'String.Interpol' )
+  * K ( ( 1 - S "}\":" ) ^ 0 , 'Interpol.Inside' )
+  * ( K ( P ":" , 'String.Interpol' ) * C ( (1 - S "}:\"") ^ 0 ) ) ^ -1
+  * K ( P "}" , 'String.Interpol' )
+
+local SingleLongInterpol =
+    K ( P "{" , 'String.Interpol' )
+  * K ( ( 1 - S "}:\r" - P "'''" ) ^ 0 , 'Interpol.Inside' )
+  * C ( P ":" * (1 - S "}:\r" - P "'''" ) ^ 0 ) ^ -1
+  * K ( P "}" , 'String.Interpol' )
+
+local DoubleLongInterpol =
+    K ( P "{" , 'String.Interpol' )
+  * K ( ( 1 - S "}:\r" - P "\"\"\"" ) ^ 0 , 'Interpol.Inside' )
+  * C ( P ":" * (1 - S "}:\r" - P "\"\"\"" ) ^ 0 ) ^ -1
+  * K ( P "}" , 'String.Interpol' )
+
+local SingleShortPureString = C ( ( P "\\'" + P "{{" + P "}}" + 1 - S "{}'" ) ^ 1 )
+
+local DoubleShortPureString = C ( ( P "\\\"" + P "{{" + P "}}" + 1 - S "{}\"" ) ^ 1 )
+
+local SingleLongPureString = C ( ( 1 - P "'''" - S "{}'\r" ) ^ 1 )
+
+local DoubleLongPureString = C ( ( 1 - P "\"\"\"" - S "{}\"\r" ) ^ 1 )
+
+local SingleShortString =
+    L ( "{\\PitonStyle{String.Short}{" )
+     * (
+           C ( P "f'" + P "F'" )
+           * ( SingleShortInterpol + SingleShortPureString ) ^ 0
+           * C ( P "'" )
+         +
+           C ( ( P "'" + P "r'" + P "R'" ) * ( P "\\'" + 1 - S "'\r" ) ^ 0 * P "'" )
+       )
+     * L ( "}}" )
+
+local DoubleShortString =
+    L ( "{\\PitonStyle{String.Short}{" )
+     * (
+           C ( P "f\"" + P "F\"" )
+           * ( DoubleShortInterpol + DoubleShortPureString ) ^ 0
+           * C ( P "\"" )
+         +
+           C ( ( P "\"" + P "r\"" + P "R\"" ) * ( P "\\\"" + 1 - S "\"\r" ) ^ 0 * P "\"" )
+       )
+     * L ( "}}" )
+
+local ShortString = SingleShortString + DoubleShortString
+
+local SingleLongString =
+      L "{\\PitonStyle{String.Long}{"
+       * (
+             C ( S "fF" * P "'''" )
+             * ( SingleLongInterpol + SingleLongPureString ) ^ 0
+             * L "}}"
+             * (
+                 EOL
+                 +
+                 L "{\\PitonStyle{String.Long}{"
+                 * ( SingleLongInterpol + SingleLongPureString ) ^ 0
+                 * L "}}"
+                 * EOL
+               ) ^ 0
+             * L "{\\PitonStyle{String.Long}{"
+             * ( SingleLongInterpol + SingleLongPureString ) ^ 0
+           +
+             C ( ( S "rR" ) ^ -1  * P "'''" * ( 1 - P "'''" - P "\r" ) ^ 0 )
+             * L "}}"
+             * (
+                 L "{\\PitonStyle{String.Long}{"
+                 * C ( ( 1 - P "'''" - P "\r" ) ^ 0 )
+                 * L "}}"
+                 * EOL
+               ) ^ 0
+             * L "{\\PitonStyle{String.Long}{"
+             * C ( ( 1 - P "'''" - P "\r" ) ^ 0 )
+          )
+       * C ( P "'''" )
+       * L "}}"
+
+local DoubleLongString =
+      L "{\\PitonStyle{String.Long}{"
+       * (
+             C ( S "fF" * P "\"\"\"" )
+             * ( DoubleLongInterpol + DoubleLongPureString ) ^ 0
+             * L "}}"
+             * (
+                 EOL
+                 +
+                 L "{\\PitonStyle{String.Long}{"
+                 * ( DoubleLongInterpol + DoubleLongPureString ) ^ 0
+                 * L "}}"
+                 * EOL
+               ) ^ 0
+             * L "{\\PitonStyle{String.Long}{"
+             * ( DoubleLongInterpol + DoubleLongPureString ) ^ 0
+           +
+             C ( ( S "rR" ) ^ -1  * P "\"\"\"" * ( 1 - P "\"\"\"" - P "\r" ) ^ 0 )
+             * L "}}"
+             * (
+                 L "{\\PitonStyle{String.Long}{"
+                 * C ( ( 1 - P "\"\"\"" - P "\r" ) ^ 0 )
+                 * L "}}"
+                 * EOL
+               ) ^ 0
+             * L "{\\PitonStyle{String.Long}{"
+             * C ( ( 1 - P "\"\"\"" - P "\r" ) ^ 0 )
+          )
+       * C ( P "\"\"\"" )
+       * L "}}"
+
+local LongString = SingleLongString + DoubleLongString
+
+local Expression =
+    P { "E" ,
+         E = ( 1 - S "{}()[]\r," ) ^ 0
+             *  (
+                  (   P "{" * V "F" * P "}"
+                    + P "(" * V "F" * P ")"
+                    + P "[" * V "F" * P "]" ) * ( 1 - S "{}()[]\r," ) ^ 0
+                ) ^ 0 ,
+         F = ( 1 - S "{}()[]\r\"'" ) ^ 0
+             * ( (
+                     P "'" * (P "\\'" + 1 - S"'\r" )^0 * P "'"
+                   + P "\"" * (P "\\\"" + 1 - S"\"\r" )^0 * P "\""
+                   + P "{"  * V "F" * P "}"
+                   + P "(" * V "F" * P ")"
+                   + P "[" * V "F" * P "]"
+                 ) * ( 1 - S "{}()[]\r\"'" ) ^ 0 ) ^ 0 ,
+      }
+
+local Param = SkipSpace * K ( identifier , '' ) * SkipSpace
+                     *  ( K ( P "=" * Expression , 'InitialValues' )
+                          +  K ( P ":" , '' ) * SkipSpace * K ( letter^1 , 'Name.Type' ))
+                  + SkipSpace * K ( alphanum ^ 1 , '' ) * SkipSpace
+
+local Params =  Param * (  K ( P "," , '' ) * Param ) ^ 0
+
+local StringDoc = K ( P "\"\"\"" , 'String.Doc' )
+                      * ( K ( (1 - P "\"\"\"" - P "\r" ) ^ 0 , 'String.Doc' ) * EOL ) ^ 0
+                      * K ( ( 1 - P "\"\"\"" - P "\r" ) ^ 0 * P "\"\"\"" , 'String.Doc' )
+                  + K ( P "'''" , 'String.Doc' )
+                      * ( K ( (1 - P "'''" - P "\r")^0 , 'String.Doc' ) * EOL ) ^ 0
+                      * K ( ( 1 - P "'''" - P "\r")^0 * P "'''" , 'String.Doc' )
+
+local CommentMath = P "$" * K ( ( 1 - S "$\r" ) ^ 1 , 'Comment.Math' ) * P "$"
+
+local Comment = L ( "{\\PitonStyle{Comment}{" )
+                * C ( P "#" ) * ( CommentMath + C ( ( 1 - S "$\r" ) ^ 1 ) ) ^ 0
+                * L ( "}}" )
+                * ( EOL + -1 )
+
+local CommentLaTeX =
+   P "##"
+   * L "{\\PitonStyle{Comment.LaTeX}{\\ignorespaces"
+   * Ct ( C ( ( 1 - P "\r" ) ^ 0 ) )
+   * L "}}"
+   * ( EOL + -1 )
+
+local DefFunction =
+   K ( P "def" , 'Keyword' )
+   * ( Space
+       * K ( identifier , 'Name.Function' )
+       * ( SkipSpace * K ( P "(" , '' ) * Params * K ( P ")" , '' ) ) ^ -1
+       * ( SkipSpace
+            * K ( ( 1 - S ":\r" )^0 , 'Post.Function' )
+            * K ( P ":" , 'Keyword' )
+            * SkipSpace
+            * ( EOL + CommentLaTeX + Comment )
+            * SkipSpace
+            * StringDoc ) ^ -1
+      ) ^ -1
+
+local ItemDict = ShortString * SkipSpace * C ( P ":" ) * K ( Expression , 'Dict.Value' )
+
+local ItemOfSet = SkipSpace * ( ItemDict + ShortString ) * SkipSpace
+
+local Set = C ( P "{" )
+            * ItemOfSet * ( C ( P "," ) * ItemOfSet )  ^ 0
+            * C ( P "}" )
+
+local Operator = K ( P "!=" + P "==" + P "<<" + P ">>" + S "-~+/*%=<>&.@|" , 'Operator')
+
+local OperatorWord = K ( P "in" + P "is" + P "and" + P "or" + P "not" , 'Operator.Word')
+
+local SyntaxPython =
+      ( ( space - P "\r" ) ^0 * P "\r" ) ^ -1 *
+      (  ( space^1 * -1 )
+         + EOL
+         + Space
+         + Escape
+         + CommentLaTeX
+         + LongString
+         + Comment
+         + ExceptionInConsole
+         + Set
+         + Delim
+         + Class * ( Space + Punct + EOL )
+         + Namespace * ( Space + Punct + EOL )
+         + ImportAs
+         + RaiseException
+         + Keyword * ( Space + Punct + EOL )
+         + DefFunction
+         + ShortString
+         + Decorator * ( Space + Punct + EOL )
+         + Operator
+         + OperatorWord * ( Space + Punct + EOL )
+         + Builtin * ( Space + Punct + EOL )
+         + Identifier
+         + Number
+         + Word
+      ) ^0 * -1
+
+local MinimalSyntax =
+  P { "S" ;
+      S = K ( (1 - P "\r" ) ^ 0 , '') + EOL * S
+    }
+
+function Parse(code)
+  local t = Ct(SyntaxPython) : match(code)
+  tex.sprint( luatexbase.catcodetables.expl , '\\__piton_begin_line:' )
+  if t then else t = Ct(MinimalSyntax) : match(code) end
+  for i = 1 , #t do
+    if type(t[i]) == 'string'
+    then
+      tex.sprint(luatexbase.catcodetables.CatcodeTableOther, t[i])
+    else
+      tex.tprint(t[i])
+    end
+  end
+  tex.sprint( luatexbase.catcodetables.expl , '\\__piton_end_line:' )
+end
+
+function ParseFile(name)
+  s = ''
+  for line in io.lines(name) do s = s .. '\r' .. line end
+  Parse(s)
+end
+
+function define_gobble_syntax(n)
+  GobbleSyntax = ( 1 - P "\r" ) ^ (-n)  * C ( ( 1 - P "\r" ) ^0 )
+               * ( C ( P "\r" )
+                   * ( 1 - P "\r" ) ^ (-n)
+                   * C ( ( 1 - P "\r" ) ^0 )
+                 ) ^ 0
+end
+
+function GobbleParse(code)
+  local t = Ct(GobbleSyntax):match(code)
+  local new_code = ""
+  for i = 1 , #t do
+    new_code = new_code .. t[i]
+  end
+  Parse(new_code)
+end
+
+function add(acc,new_value)
+  return acc + new_value
+end
+
+--[[ The following LPEG returns as capture the minimal number of spaces at
+the beginning of the lines of code]]
+AutoGobbleSyntax =
+    ( space ^ 0 * P "\r" ) ^ -1
+    * Cf (
+           (
+             ( P " " ) ^ 0 * P "\r"
+             +
+             Cf ( Cc(0) * ( P " " * Cc(1) ) ^ 0 , add )
+             * ( 1 - P " " ) * ( 1 - P "\r" ) ^ 0 * P "\r"
+           ) ^ 0
+           *
+           ( Cf ( Cc(0) * ( P " " * Cc(1) ) ^ 0 , add )
+           * ( 1 - P " " ) * ( 1 - P "\r" ) ^ 0 ) ^ -1 ,
+           math.min
+         )
+
+function AutoGobbleParse(code)
+  local n = AutoGobbleSyntax:match(code)
+  if n==0
+  then Parse(code)
+  else define_gobble_syntax(n)
+       GobbleParse(code)
+  end
+end
+
+--[[ The following LPEG returns as capture the number of spaces at the last line,
+that is to say begin the \end{Piton} ]]
+
+EnvGobbleSyntax =
+       ( ( 1 - P "\r" ) ^ 0 * P "\r" ) ^ 0
+         * Cf ( Cc(0) * ( P " " * Cc(1) ) ^ 0 , add ) * -1
+
+function EnvGobbleParse(code)
+  local n = EnvGobbleSyntax:match(code)
+  if n==0
+  then Parse(code)
+  else define_gobble_syntax(n)
+       GobbleParse(code)
+  end
+end
+\end{luacode*}
 
 \endinput
 %%