Implemented Most Recent

[mairbek]

For issue #64.

[cloudbees-pull-request-builder]

RxJava-pull-requests #6 SUCCESS
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[benjchristensen]

Man it is hard to understand the difference between Latest, Next, MostRecent etc using MSDN docs ...

[benjchristensen]

Trying to figure out the difference between Observable.Latest (http://msdn.microsoft.com/en-us/library/hh212115(v=vs.103).aspx) and Observable.MostRecent (http://msdn.microsoft.com/en-us/library/hh229751(v=vs.103).aspx) other than the latter having an initialValue.

Both return IEnumerable<TSource> and both say "Samples the most recent value in an observable sequence."

The Observable.Next operator says "Samples the next value (blocking without buffering) from in an observable sequence." and also returns IEnumerable<TSource>.

[benjchristensen]

My understanding of these operators are:

• Latest
  • will cache the latest value and return immediately when iterator.next() is called
  • or block if no value is cached until next value
  • when the value is emitted it is removed from the cache so only emitted once
• Next
  • will not cache the latest value so will block until next value
• MostRecent
  • will cache the latest value and return immediately when iterator.next() is called
  • or block if no value is cached until next value
  • the last value is always retained so if you subscribe to it multiple times it will keep returning the "most recent" value
  • the initialValue guarantees it will never wait and immediately return

[benjchristensen]

This pull request looks good ... merging.