> They can be useful for certain constructions, but they don’t really enable anything amazing that you can’t do otherwise, just with a slightly different algori

> They can be useful for certain constructions, but they don’t really enable anything amazing that you can’t do otherwise, just with a slightly different algorithm. One really nice property of laziness is dealing with data larger than RAM. A couple of months ago I wrote some ML processing of the wikipedia XML in Clojure. In about 5 lines, I had a lazy sequence of every <Article> tag from the XML. Then I can (map my-fn all-articles-from-wikipedia), without blowing the heap (the wikipedia XML was like ~10GB, zipped). Yes, it's possible to do non-lazy, but this was cleaner and simpler. One algorithmic advantage of lazy seqs is that (map foo (map bar (map baz my-big-seq))) makes only one pass over the data, as opposed to 3 when non-lazy.