Bugfix: throwing error when trying to print valid regexps.

* regex.c (print_rec): Only dianose "bad object in regex syntax"
for some atom other than nil, which denotes an empty (sub)expression,
like what results from #// or #/a|/ and such.

2 files changed, 9 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 60472e7c..416496b2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2015-04-19  Kaz Kylheku  <kaz@kylheku.com>
 
+	Bugfix: throwing error when trying to print valid regexps.
+
+	* regex.c (print_rec): Only dianose "bad object in regex syntax"
+	for some atom other than nil, which denotes an empty (sub)expression,
+	like what results from #// or #/a|/ and such.
+
+2015-04-19  Kaz Kylheku  <kaz@kylheku.com>
+
 	Do not allow unrecognized escapes in regex.
 
 	* parser.l (REGOP): New regex alias for matching all regex
diff --git a/regex.c b/regex.c
index fade9449..b8e7daec 100644
--- a/regex.c
+++ b/regex.c
@@ -1831,7 +1831,7 @@ static void print_rec(val exp, val stream)
     } else {
       uw_throwf(error_s, lit("bad operator in regex syntax: ~s"), sym, nao);
     }
-  } else {
+  } else if (exp != nil) {
     uw_throwf(error_s, lit("bad object in regex syntax: ~s"), exp, nao);
   }
 }