(def data1 "aaab")
(def data2 "aaaba")
(def data3 "bbba")
(def pattern #"a+b")

;; re-find looks for the pattern ANYWHERE in the string
(def b1 (some? (re-find pattern data1)))
;; b1 is true
(def b2 (some? (re-find pattern data2)))
;; b2 is true
(def b3 (some? (re-find pattern data3)))
;; b3 is false

(println "b1 is" b1)
(println "b2 is" b2)
(println "b3 is" b3)
;; re-matches would say false for data2: it needs the whole string
(println "re-matches on data2 is" (some? (re-matches pattern data2)))