awk: prn returns nil.

* stdlib/awk.tl (awk-state prn): Return nil in the no-argument
case instead of returning whatever put-string returns.

* tests/015/awk-misc.tl: New file.

* txr.1: Documented.

3 files changed, 17 insertions, 1 deletions

diff --git a/stdlib/awk.tl b/stdlib/awk.tl
index e6ce26f9..197dbf38 100644
--- a/stdlib/awk.tl
+++ b/stdlib/awk.tl
@@ -188,7 +188,8 @@
             (put-string `@(car a)`)
             (put-string (if (set next (cdr a)) self.ofs self.ors))))
     (t (put-string self.rec)
-       (put-string self.ors))))
+       (put-string self.ors)
+       nil)))
 
 (defmeth sys:awk-state ensure-stream (self kind path mode)
   (hash-update-1 self.streams
diff --git a/tests/015/awk-misc.tl b/tests/015/awk-misc.tl
new file mode 100644
index 00000000..af61857d
--- /dev/null
+++ b/tests/015/awk-misc.tl
@@ -0,0 +1,10 @@
+(load "../common")
+
+(let ((*stdout* *stdnull*))
+  (test
+    (build
+      (awk
+        (:inputs '(""))
+        (t (add (prn 1 2 3))
+           (add (prn)))))
+    (nil nil)))
diff --git a/txr.1 b/txr.1
index a89ef396..4ac510d9 100644
--- a/txr.1
+++ b/txr.1
@@ -70174,6 +70174,11 @@ Thus if the value is
 the output for that argument is an empty string, rather than the text
 .strn nil .
 
+The
+.code prn
+function returns
+.codn nil .
+
 .coNP Macro @ next
 .synb
 .mets (next)