code: private void eatExpression() {
          List segments = new ArrayList();
          eatSplicedRange(segments);
          list.add(segments);
          if (tokenizer.hasMoreTokens()) {// ∈
              tokenizer.peekToken(0, TokenKind.COMMA);
              tokenizer.nextToken();
              eatExpression();
          }
      }
docs: Expression -> (SplicedRange "," )(Expression | ∈)