MapReduce result vivification

[seancribbs]

Reference: https://gist.github.com/38eb017bf86d055d2e4e

Either automatic, implicit, or explicit reification of MapReduce results into appropriate Document instances.

Possibilities:

• Detect presence of _type field in results, instantiate as appropriate.
• Explicit #to_docs method.
• ...? (add more ideas in comments)

[tpjg]

I was looking for this functionality. I'm a complete newbie to Riak and it took me quite a while to figure out how the whole MapReduce stuff worked. But if you're trying to achieve this for a single (known) type, I think it could be as simple as adding the following as the last stage to MapReduce:

r = Riak::MapReduce.new .....
map("function(v){ return [v.key]; }", :keep => true).run

results = Type.find(r)