anchor.diff:  //二元位运算
   bitwise_op : BITWISE_AND | BITWISE_OR | BITWISE_EXCLUSIVE_OR;
   //二元运算符
  -binary_op : arithmetic_op | bitwise_op | EXPONENITIATION;
  +binary_op : arithmetic_op | bitwise_op | EXPONENITIATION | RANGE;
   //一元运算符
   unary_op : BITWISE_COMPLEMENT;
   //数字
  
positive.code: soft_rule : (DECIMAL | integer ) CONDITION hard_rule;
  
  //
  meta_rule : META_OP (MINUS)? CONSTANT SLASH natural_number FULLSTOP;
  
  //ASP4QA程序
  lpmln_rule : (hard_rule | soft_rule | meta_rule)*;
negative.code: 
  
  //函数
  function : IDENTIFIER term;
  //简单项，缺_,#sup,#inf
  simpleterm : integer | CONSTANT | STRING | VAR;
  //元组
  tuple : | COMMA | ( COMMA term )+ ;
  
  //范围枚举
  //interval : (integer | VAR) RANGE (integer | VAR);
  //逐个枚举
  pooling :  (SEMICOLON term)+;
  
  //项
  //term : VAR | CONSTANT | integer | arithmethic_expr | function | STRING;
  term : (simpleterm | function | arithmethic_expr | LPAREN term RPAREN) (tuple | pooling);
  
  //原子
  atom :
      CONSTANT |
      IDENTIFIER LPAREN term (COMMA term)* RPAREN;
  
  //文字
  literal : atom | MINUS atom | NAF_NOT literal | comparison_literal;
  