Evaluate properties

Found here
https://groups.google.com/forum/m/#!topic/haxelang/mZxvWcT4ZBc

Can we do something to make it more clear?

Start by reading the linked Google Groups discussion to understand which property behavior or explanation is unclear. Locate the corresponding properties section in the Haxe Manual, then define the needed clarification and update the documentation so the behavior is understandable without relying on the external discussion.

Written by the indexing model from the issue text.