grammar

/* 
 * Assert language Grammar
 * The notation is a mixture of EBNF and my preferences.
 *
 * +───────────────────+────────────+
 * | Usage             | Notation   |
 * +───────────────────+────────────+
 * | definition        | ->         |
 * | concatenation     | ,          |
 * | termination       | ;          |
 * | alternation       | |          |
 * | optional          | [ ... ]    |
 * | repetition        | { ... }    |
 * | grouping          | ( ... )    |
 * | terminal string   | " ... "    |
 * +───────────────────+────────────+
 */
   
grammar -> { "dump" define | "assert" "(" assign ")" } ;

assign -> ["inv"] ident "=" expression | 
          ["inv"] array "=" expression ;
          
define -> ident "(" [ident] {"," ident } ")" block ;

block  -> statement | "{" statement  { statement } "}" ;

statement -> "assert" "(" ( assign | "return"  expression ) ")"  |   
             "if"     "(" expression ")" block ["else" block] |
             "while"  "(" expression ")" block |
             function ;

function -> (ident | "out" | "in") "(" [expression] {"," expression } ")" ;
              
array -> ident "[" expression "]" ;

expression -> logical {("||"|"&&") logical} ;

logical -> boolean [(">"|"<"|">="|"<="|"=="|"!=") boolean] ;

boolean -> [+|-] additive {(+|-) additive} ;

additive -> factor {("*"|"/") factor} ;

factor -> exponent ["^" exponent] ;

exponent -> number              | 
            ident               | 
            array               |
            function            |
            "!" exponent        |
            ("+"|"-") exponent  ;