clojure.core/re-seq

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Type: function Added: Clojure 1.0 Examples: 6 Runnable: 4

([re s])

Returns a lazy sequence of successive matches of pattern in string, using java.util.regex.Matcher.find(), each such match processed with re-groups.

Examples

by nipra on 2010-07-13 ▶

(re-seq #"\d" "clojure 1.1.0") ("1" "1" "0")

by ghoseb on 2010-07-13 ▶

;; Get a sequence of words out of a string. (re-seq #"\w+" "mary had a little lamb") ("mary" "had" "a" "little" "lamb")

by jafingerhut on 2011-12-16 . May have evaluation errors. ▶

;; Parenthesized groups in the regex cause each returned match to be a ;; vector of matched strings. See re-find for more examples. (def line " RX pkts:18 err:5 drop:48") #'user/line (re-seq #"(\S+):(\d+)" line) (["pkts:18" "pkts" "18"] ["err:5" "err" "5"] ["drop:48" "drop" "48"])

by jafingerhut on 2013-09-13 ▶

;; Note: See clojure.core/subs for discussion of behavior of substrings ;; holding onto references of the original strings, which can ;; significantly affect your memory usage in some cases.

by manishkumarmdb on 2016-08-11 ▶

;; separate with Camel case words and digits and ;; join with single white-space character (clojure.string/join " " (re-seq #"[A-Z][a-z]+|[0-9]+" "ManishKumar12332")) "Manish Kumar 12332"

by reborg on 2018-02-23 . May have evaluation errors. ▶

;; re-seq requires the string to be in memory. What if the string is in a file ;; many GB in size? You can roll a "line-seq of re-seq each line" or use: (defn restream-seq [^java.util.regex.Pattern re ^java.io.InputStream is] (let [s (java.util.Scanner. is)] ((fn step [] (if-let [token (.findInLine s re)] (cons token (lazy-seq (step))) (when (.hasNextLine s) (.nextLine s) (step))))))) ;; first 10 digits of Pi out of the book (1M available) (let [pi-book "https://www.gutenberg.org/files/50/50.txt"] (with-open [is (.openStream (java.net.URL. pi-book))] (doall (sequence (comp cat (map str) (take 10)) (restream-seq #"\d{10}" is))))) ; ("1" "4" "1" "5" "9" "2" "6" "5" "3" "5")

See also

• clojure.core/re-find (3)
• clojure.core/re-groups (0)
• clojure.core/re-pattern
• clojure.core/re-matcher (0)
• clojure.core/re-matches (3)
• clojure.string/split (4)
• clojure.core/subs (3)

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