// Denne grammatik er til et SUBSET af bibtex!!
// understøtter KUN entries af formen:

// @STRING{RMP="Rev. Mod. Phys."}
// ELLER
// @Book{abramowitz+stegun,
//   author =       "Milton Abramowitz and Irene A. Stegun",
//   title =        "Handbook of Mathematical Functions with
//                   Formulas, Graphs, and Mathematical Tables",
//   publisher =    "Dover",
//   year =         1964,
//   address =      "New York",
//   edition =      "ninth Dover printing, tenth GPO printing",
//   isbn =         "0-486-61272-4"
// }

 

// TRIVIA
// Note that the lexical language is both non-regular 
// (because braces must balance) 
// and context-sensitive (because { can mean different 
// things depending on its syntactic context).
// JUNK = (~["@", "\n", " ", "\r", "\t"])+
// baseret på http://www.gerg.ca/software/btOOL/doc/bt_language.html
// ændringer: () er ikke entry opener/closer, kun {}

// top level
LEXING:
SKIP: 
(
		<"%" (~["\n"])* > 
	| 
		" " 
	| 
		"\r" 
	| 
		"\t" 
	|
		"\n"
)

TOKENS:

ABREV = ("@" ("S"|"s") ("T"|"t") ("R"|"r") ("I"|"i") ("N"|"n") ("G"|"g") )
AT = "@"
//NEWLINE = "\n"
NUMBER = (["0"-"9"])+
STRING   = ("\"" (~["\""])+ "\"")
NAME     = (["a"-"z", "A"-"Z", "0"-"9", "!", "$", "&", "*", "+", "-", 
             ".", "/", ":", ";", "<", ">", "?", "[", "]", "^", "_", "`", "|"])+
LBRACE = "{"
RBRACE = "}"
LPAR = "("
RPAR = ")"
EQUALS = "="
COMMA  = ","

GRAMMAR:

Bibfile ::= Entries
	;

Entries  ::= Entry (Entries)? 
	;

Entry    ::= AT NAME Body 
           | ABREV LBRACE NAME EQUALS STRING RBRACE
					
	;

Body     ::= LBRACE Contents RBRACE
	;
	
Contents ::= NAME COMMA Fields     
         | NUMBER COMMA Fields 
	;

// for regular entries         
// for macro definition Entries         
// for preamble entries        

Fields   ::= Field (COMMA Fields)?
	;

Field    ::= NAME EQUALS Value 
	;

Value   ::= STRING | NUMBER | NAME
	;