initial file ;

file
    = declaration+                                    # File
    ;

declaration
    = NONTERMINAL EQUALS prod (BAR prod)* SEMICOLON   # Production
    | INITIAL NONTERMINAL SEMICOLON                   # Initial
    ;

prod
    = regexps HASH TERMINAL (COMMA (SHIFT|REDUCE) TERMINAL)* # ProductionRhs
    ;

regexps 
    = (regexp (regexp | STAR | PLUS | OPTIONAL)*)?         # Concatenation 
    ;

regexp
    = (TERMINAL | NONTERMINAL | SHIFT | REDUCE | INITIAL)  # Terminal
    | LPAREN regexps (BAR regexps)* RPAREN                 # Union
    ;