length -package:vector package:streaming

length :: Monad m => Stream (Of a) m r -> m (Of Int r)
streaming Streaming.Prelude
Run a stream, keeping its length and its return value. 
>>> S.print $ mapped S.length $ chunksOf 3 $ S.each [1..10]
3
3
3
1
length_ :: Monad m => Stream (Of a) m r -> m Int
streaming Streaming.Prelude
Run a stream, remembering only its length: 
>>> runIdentity $ S.length_ (S.each [1..10] :: Stream (Of Int) Identity ())
10