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EBNF for "dhigh"
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PROGRAM = DECLARATION BODY ;

DECLARATION = { TYPE IDENTIFIER  ";" } ;

TYPE = "int" | "bool" | "void" ;

IDENTIFIER = {CHAR} LETTER { ( CHAR | LETTER) } ;

CHAR = LETTER | NUMBER ;

BODY = { FUNCTION } ;

FUNCTION = DECLARATION "(" { DECLARATION } ")" "{" FUNCTIONBODY "}" ;

FUNCTIONBODY = { ( ASSIGNMENT | QUERY | LOOP ) } ;

ASSIGNMENT = IDENTIFIER "=" ( { NUMBER } | BOOL | CALC ) ";" ;

CALC = ( IDENTIFIER | { NUMBER } ) CALCOP ( IDENTIFIER | { NUMBER } ) { CALCOP ( IDENTIFIER | { NUMBER } ) } ;

QUERY = "if" CONDITION { ( "AND" | "OR ) CONDITION } "{" FUNCTIONBODY "}" ;

CONDITION = "(" ( BOOL | IDENTIFIER | IDENTIFIER CONDOP ( BOOL | IDENTIFIER | { NUMBER } ) ) ")" ;

LOOP = WHILE | FOR ;

WHILE = "while" CONDITION { ( "AND" | "OR ) CONDITION } "{" FUNCTIONBODY "}" ;

WHILE = "for" "(" DECLARATION ";" CONDITION ";" ASSIGNMENT ")" "{" FUNCTIONBODY "}" ;

LETTER = "A" | "B" | "C" | "D" | "E" | "F" | "G" | "H" | "I" | "J" | "K" | "L" | "M" | "N" | "O" | "P" | "Q" | "R" | "S" | "T" | "U" | "V" | "W" | "X" | "Y" | "Z" ;

NUMBER = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ;

CONDOP = "==" | "!=" | ">" | "<" | ">=" | "<=" ;

CALCOP = "+" | "-" | "*" | "/" | "%" ;

BOOL = "true" | "false" ;



(*
Comments:
- Bool only int => "true" = 1, "false" != 1
- "main"-method (IDENTIFIER = "main") is called as first method
*)