ident-list.eag

S <+ IdentList>: IdentList < , IdentList>.

letter = 'a' | 'b'.

letter: <+ 'a': letter> 'a' | <+ 'b': letter> 'b' .

digit = '0' | '1'.

digit: <+ '0': digit> '0' | <+ '1': digit> '1' .

ident* = letter | ident letter | ident digit.

ident* <+ ident>:
    letter <letter>
    <letter, ident>
        { <- ident, + ident1>
            letter <letter>  <ident letter, ident1>
        | <- ident, + ident1>
            digit <digit>  <ident digit, ident1>
        } <- ident, + ident>.

IdentList = | IdentList ident.

IdentList:
    { <- IdentList, +  IdentList1>
        ident <ident> FindObject <IdentList, ident, 'NIL'> <IdentList ident, IdentList1>
    } <- IdentList, + IdentList>.

IdentNil = ident | 'NIL'.

FindObject:
    <- : IdentList, - ident, + 'NIL': IdentNil>
  | <- IdentList ident: IdentList, - ident, + ident: IdentNil>
  | <- IdentList !ident: IdentList, - ident, + IdentNil: IdentNil>
      FindObject <IdentList, ident, IdentNil>.