Github user vrozov commented on the issue:
https://github.com/apache/drill/pull/1236
IMO, neither `append` or `appendField` is a good choice (otherwise it is
necessary to change `startNode/endNode` to `appendStart/EndNode`). It is either
`field` or `visitField` and should follow visitor design pattern. It may be
also good to change `listField` to the same name used for `Boolean` and
`String`.---
