`clojure.core/pr`¶

Type: function Added: Clojure 1.0 Examples: 4 Runnable: 2

([] [x] [x & more])

Prints the object(s) to the output stream that is the current value of out. Prints the object(s), separated by spaces if there is more than one. By default, pr and prn print in a way that objects can be read by the reader

Examples¶

by srid on 2011-09-07

by Dimagog on 2015-02-04 . May have evaluation errors.

by jafingerhut on 2016-08-06 . May have evaluation errors.

;; WARNING: Clojure's keyword and symbol functions allow you to create
;; values that cannot be printed then later read and recreate those same
;; values.

;; For most common symbols and keywords, they round-trip through pr
;; then read-string, as this example shows.
(read-string (with-out-str (pr {:a 1, :b 2})))
{:a 1, :b 2}

;; But these values do not round-trip through the same steps:
(def kw1 (keyword "foo bar"))
#'user/kw1
kw1
:foo bar
(def s2 (with-out-str (pr {kw1 1, :b 2})))
#'user/s2
s2
"{:foo bar 1, :b 2}"
(read-string s2)

RuntimeException Map literal must contain an even number of forms  clojure.lang.Util.runtimeException (Util.java:221)

;; Similarly for a symbol like (symbol "a;b")
(def sym1 (symbol "a;b"))
#'user/sym1
sym1
a;b
(def s3 (with-out-str (pr sym1)))
#'user/s3
s3
"a;b"
(read-string s3)
a

;; If you wish to transmit data that may contain such values, one suggestion
;; is to use the transit library: https://github.com/cognitect/transit-format

;; It is much faster and formally specified.

Note by jcburley¶

"Readable by the reader" means, for example, that a string is printed with surrounding double quotes and with quotes, backslashes, and nonprinting characters being escaped via a backslash prefix.

clojure.core/pr¶

Examples¶

Note by jcburley¶

See also¶

`clojure.core/pr`¶