On Monday, 27 August 2012 at 15:00:11 UTC, deadalnix wrote:
/!\ Shameless autopromotion incoming /!\
I have recently put some effort into exploring alternatives to
visitor pattern and see what can be done in D. I ended up with
a solution which is a real improvement compared to plein old
visitor pattern and wanted to share this here.
I think this is short enough to be a good example to show what
can be done with D capabilities.
http://www.deadalnix.me/2012/08/25/visitor-pattern-revisited-in-d/
This is nice use of d magic. If the implementation could
recompute the functions pointers during compilation, this seems
as nice generally function. This makes me thing of computed goto
(to functions)
One possibility to achieve this result for visitor is to use
mixin.
I would mixin implementation of accept method into very node
super class. This is to avoid code duplication.
Secondly, I would mixin implementation of opDispatch that simply
does nothing/throws to every implementation of visitor. This is
to avoid empty implementations of visit methods which are not
needed for particular visitor.
