From 62e52bf41ddc0052994d827e3942b46a4c3cb79a Mon Sep 17 00:00:00 2001
From: Alexis King <lexi.lambda@gmail.com>
Date: Tue, 27 Jan 2015 08:31:40 -0800
Subject: [PATCH] Add writeln and println functions to complement displayln

---
 .../scribblings/reference/write.scrbl         | 19 ++++++++++++++-
 racket/collects/racket/private/misc.rkt       | 23 ++++++++++++++++++-
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/pkgs/racket-doc/scribblings/reference/write.scrbl b/pkgs/racket-doc/scribblings/reference/write.scrbl
index 65e457097f..bb096ac341 100644
--- a/pkgs/racket-doc/scribblings/reference/write.scrbl
+++ b/pkgs/racket-doc/scribblings/reference/write.scrbl
@@ -65,12 +65,29 @@ conventions should be assumed for @racket[print], so that environments
 are free to modify the actual output generated by @racket[print] in
 any way.}
 
+@defproc[(writeln [datum any/c] [out output-port? (current-output-port)])
+         void?]{
+
+The same as @racket[(write datum out)] followed by @racket[(newline out)].}
 
 @defproc[(displayln [datum any/c] [out output-port? (current-output-port)])
          void?]{
 
 The same as @racket[(display datum out)] followed by @racket[(newline out)],
-which is similar to @as-index{@tt{println}} in Pascal or Java.}
+which is similar to @tt{println} in Pascal or Java.}
+
+@defproc[(println [datum any/c] [out output-port? (current-output-port)]
+                  [quote-depth (or/c 0 1) 0])
+         void?]{
+
+The same as @racket[(print datum out quote-depth)] followed by
+@racket[(newline out)].
+
+This is not equivalent to @tt{println} in other languages because, by default,
+it uses the printing conventions of @racket[write]. For a closer analog, use
+@racket[displayln] instead.}
+
+@history[#:changed "6.1.1.8" @elem{Added @racket[writeln] and @racket[displayln].}]
 
 @defproc[(fprintf [out output-port?] [form string?] [v any/c] ...) void?]{
 
diff --git a/racket/collects/racket/private/misc.rkt b/racket/collects/racket/private/misc.rkt
index ae421ca9b8..7f6512e365 100644
--- a/racket/collects/racket/private/misc.rkt
+++ b/racket/collects/racket/private/misc.rkt
@@ -174,6 +174,15 @@
 
   (define (port? x) (or (input-port? x) (output-port? x)))
 
+  (define writeln
+    (case-lambda
+     [(v) (writeln v (current-output-port))]
+     [(v p) 
+      (unless (output-port? p)
+        (raise-argument-error 'writeln "output-port?" 1 v p))
+      (write v p)
+      (newline p)]))
+  
   (define displayln
     (case-lambda
      [(v) (displayln v (current-output-port))]
@@ -182,6 +191,18 @@
         (raise-argument-error 'displayln "output-port?" 1 v p))
       (display v p)
       (newline p)]))
+  
+  (define println
+    (case-lambda
+      [(v) (println v (current-output-port) 0)]
+      [(v p) (println v p 0)]
+      [(v p d)
+       (unless (output-port? p)
+         (raise-argument-error 'println "output-port?" 1 v p d))
+       (unless (and (number? d) (or (= 0 d) (= d 1)))
+         (raise-argument-error 'println "(or/c 0 1)" 2 v p d))
+       (print v p d)
+       (newline p)]))
 
   ;; -------------------------------------------------------------------------
 
@@ -232,7 +253,7 @@
              path-list-string->path-list find-executable-path
              collection-path collection-file-path load/use-compiled
              guard-evt channel-get channel-try-get channel-put
-             port? displayln
+             port? writeln displayln println
              find-library-collection-paths
              find-library-collection-links
              bytes-environment-variable-name?