Benchmark data for StackOverflow question: http://stackoverflow.com/questions/39654782/how-do-i-check-whether-a-string-is-uppercase-or-not-in-clojure/39656499#39656499

bench-string-uppercase-check.clj

(set! *warn-on-reflection* true)

;; 3 competing implementations which test if a string is uppercase (note that the StringUtils one has some caveats regarding its semantics)
(defn p1 [^String s]
  (= s (str/upper-case s)))
(defn p2 [^String s]
  (every? (fn [^Character c] (Character/isUpperCase c)) s))
(import org.apache.commons.lang3.StringUtils)
(defn p3 [^String s]
  (StringUtils/isAllUpperCase s))


(require '[criterium.core :as bench])
(bench/bench 
  (let [p p1] 
    (p "coucou")
    (p "Coucou")
    (p "")
    (p "AAAAAAAAAAAAAAAAAAAAAAAAAAAAA")
    (p "    AAAAA   a")
    (p "FA3AEAAAAAAAAA4AAAAAAABAAAAAAb")
    ))
;Evaluation count : 74244840 in 60 samples of 1237414 calls.
;             Execution time mean : 782.701501 ns
;    Execution time std-deviation : 97.513671 ns
;   Execution time lower quantile : 606.340774 ns ( 2.5%)
;   Execution time upper quantile : 959.838592 ns (97.5%)
;                   Overhead used : 2.280109 ns

(bench/bench 
  (let [p p2] 
    (p "coucou")
    (p "Coucou")
    (p "")
    (p "AAAAAAAAAAAAAAAAAAAAAAAAAAAAA")
    (p "    AAAAA   a")
    (p "FA3AEAAAAAAAAA4AAAAAAABAAAAAAb")
    ))
;Evaluation count : 30735540 in 60 samples of 512259 calls.
;             Execution time mean : 2.149382 µs
;    Execution time std-deviation : 244.568748 ns
;   Execution time lower quantile : 1.654448 µs ( 2.5%)
;   Execution time upper quantile : 2.591681 µs (97.5%)
;                   Overhead used : 2.280109 ns
;
;Found 1 outliers in 60 samples (1.6667 %)
;	low-severe	 1 (1.6667 %)
; Variance from outliers : 75.4844 % Variance is severely inflated by outliers

(bench/bench 
  (let [p p3] 
    (p "coucou")
    (p "Coucou")
    (p "")
    (p "AAAAAAAAAAAAAAAAAAAAAAAAAAAAA")
    (p "    AAAAA   a")
    (p "FA3AEAAAAAAAAA4AAAAAAABAAAAAAb")
    ))
;Evaluation count : 1324237920 in 60 samples of 22070632 calls.
;             Execution time mean : 51.473188 ns
;    Execution time std-deviation : 5.440066 ns
;   Execution time lower quantile : 42.837131 ns ( 2.5%)
;   Execution time upper quantile : 61.430209 ns (97.5%)
;                   Overhead used : 2.280109 ns
;
;Found 1 outliers in 60 samples (1.6667 %)
;	low-severe	 1 (1.6667 %)
; Variance from outliers : 72.0795 % Variance is severely inflated by outliers

;; Context:

;Hardware Overview:
;  Model Name:	MacBook Air
;  Model Identifier:	MacBookAir7,1
;  Processor Name:	Intel Core i7
;  Processor Speed:	2,2 GHz
;  Number of Processors:	1
;  Total Number of Cores:	2
;  L2 Cache (per Core):	256 KB
;  L3 Cache:	4 MB
;  Memory:	8 GB

;System Software Overview:
;  System Version:	OS X 10.10.5 (14F27)
;  Kernel Version:	Darwin 14.5.0
;  Boot Volume:	Macintosh HD
;  Boot Mode:	Normal
;  Secure Virtual Memory:	Enabled
;  Time since boot:	35 minutes

; Java version
;java version "1.8.0_05"
;Java(TM) SE Runtime Environment (build 1.8.0_05-b13)
;Java HotSpot(TM) 64-Bit Server VM (build 25.5-b02, mixed mode)

;Clojure 1.8.0