Deal with bad quote syntax.

* eval.c (op_quote): Throw error on bad syntax.

* lib.c (obj_print, obj_pprint): Do not hide bad quote syntax
using ' notation; print it using ordinary notation.

3 files changed, 15 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 96aee8ce..7d06a0ee 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2015-05-03  Kaz Kylheku  <kaz@kylheku.com>
+
+	Deal with bad quote syntax.
+
+	* eval.c (op_quote): Throw error on bad syntax.
+
+	* lib.c (obj_print, obj_pprint): Do not hide bad quote syntax
+	using ' notation; print it using ordinary notation.
+
 2015-05-01  Kaz Kylheku  <kaz@kylheku.com>
 
 	Move initialization calls to more suitable place.
diff --git a/eval.c b/eval.c
index 0149c764..87a6b875 100644
--- a/eval.c
+++ b/eval.c
@@ -1102,6 +1102,10 @@ static val eval_prog1(val forms, val env, val ctx_form)
 
 static val op_quote(val form, val env)
 {
+  val d = cdr(form);
+
+  if (!consp(d) || cdr(d))
+    eval_error(form, lit("bad quote syntax"), nao);
   return second(form);
 }
 
diff --git a/lib.c b/lib.c
index 6f82063a..0503d615 100644
--- a/lib.c
+++ b/lib.c
@@ -6700,7 +6700,7 @@ val obj_print(val obj, val out)
     {
       val sym = car(obj);
 
-      if (sym == quote_s) {
+      if (sym == quote_s && consp(cdr(obj)) && !(cdr(cdr(obj)))) {
         put_char(chr('\''), out);
         obj_print(second(obj), out);
       } else if (sym == sys_qquote_s) {
@@ -6894,7 +6894,7 @@ val obj_pprint(val obj, val out)
     {
       val sym = car(obj);
 
-      if (sym == quote_s) {
+      if (sym == quote_s && consp(cdr(obj)) && !(cdr(cdr(obj)))) {
         put_char(chr('\''), out);
         obj_print(second(obj), out);
       } else if (sym == sys_qquote_s) {