Whoa. I didn't dismiss any benchmarks, and I'm happy to back up any of what I've said with real-life experiences.
For example, I was working on a system a few weeks back that involves loading several-hundred GB CSV files. I wrote it in a functional style, with several map and filter operations over each of the rows. I was able to program the logic viewing the entire CSV file as a single lazy sequence to transform.
After profiling I ended up using Java arrays instead of Clojure vectors as the primary data format for records in the system: given the fact that this app was IO-bound, this resulted in about 20% improvement for that particular use case.
However, because Clojure is capable of treating arrays as sequences polymorphically, the change required very few modifications to my code and I was able to maintain a functional style.
For example, I was working on a system a few weeks back that involves loading several-hundred GB CSV files. I wrote it in a functional style, with several map and filter operations over each of the rows. I was able to program the logic viewing the entire CSV file as a single lazy sequence to transform.
After profiling I ended up using Java arrays instead of Clojure vectors as the primary data format for records in the system: given the fact that this app was IO-bound, this resulted in about 20% improvement for that particular use case.
However, because Clojure is capable of treating arrays as sequences polymorphically, the change required very few modifications to my code and I was able to maintain a functional style.