* parser.l (lisp_parse): Bugfix: the error_stream argument

must be checked to be a stream before we plant it in place
of std_error, otherwise we will get a type exception thrown
lower down, which leads to runaway recursion as TXR tries
to print the error messages on std_error.

* dep.mk: Regenerated.

3 files changed, 23 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index dab14119..a01c0ef0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 2014-10-19  Kaz Kylheku  <kaz@kylheku.com>
 
+	* parser.l (lisp_parse): Bugfix: the error_stream argument
+	must be checked to be a stream before we plant it in place
+	of std_error, otherwise we will get a type exception thrown
+	lower down, which leads to runaway recursion as TXR tries
+	to print the error messages on std_error.
+
+	* dep.mk: Regenerated.
+
+2014-10-19  Kaz Kylheku  <kaz@kylheku.com>
+
 	* parser.y (r_exprs): New grammar symbol. r_exprs uses
 	left-recursive rules to avoid filling the yacc stack, and
 	returns the items in reverse order. The output of each
diff --git a/dep.mk b/dep.mk
index 071897e6..bc7458e0 100644
--- a/dep.mk
+++ b/dep.mk
@@ -1,5 +1,5 @@
 ./txr.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./stream.h $(top_srcdir)/./gc.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./parser.h $(top_srcdir)/./match.h $(top_srcdir)/./utf8.h $(top_srcdir)/./debug.h $(top_srcdir)/./syslog.h $(top_srcdir)/./eval.h $(top_srcdir)/./regex.h $(top_srcdir)/./arith.h $(top_srcdir)/./txr.h
-./lex.yy.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./gc.h $(top_srcdir)/./stream.h $(top_srcdir)/./utf8.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./hash.h $(top_srcdir)/./parser.h y.tab.h
+./lex.yy.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./gc.h $(top_srcdir)/./stream.h $(top_srcdir)/./utf8.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./hash.h $(top_srcdir)/./parser.h $(top_srcdir)/./eval.h y.tab.h
 ./y.tab.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./regex.h $(top_srcdir)/./utf8.h $(top_srcdir)/./match.h $(top_srcdir)/./hash.h $(top_srcdir)/./eval.h $(top_srcdir)/./stream.h $(top_srcdir)/./parser.h
 ./match.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./gc.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./regex.h $(top_srcdir)/./stream.h $(top_srcdir)/./parser.h $(top_srcdir)/./txr.h $(top_srcdir)/./utf8.h $(top_srcdir)/./filter.h $(top_srcdir)/./hash.h $(top_srcdir)/./debug.h $(top_srcdir)/./eval.h $(top_srcdir)/./match.h
 ./lib.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./gc.h $(top_srcdir)/./arith.h $(top_srcdir)/./rand.h $(top_srcdir)/./hash.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./stream.h $(top_srcdir)/./utf8.h $(top_srcdir)/./filter.h $(top_srcdir)/./eval.h $(top_srcdir)/./sysif.h $(top_srcdir)/./regex.h
diff --git a/parser.l b/parser.l
index 7b2ffde1..92a3b08e 100644
--- a/parser.l
+++ b/parser.l
@@ -48,6 +48,7 @@
 #include "unwind.h"
 #include "hash.h"
 #include "parser.h"
+#include "eval.h"
 #include "y.tab.h"
 
 #define YY_INPUT(buf, result, max_size)           \
@@ -996,24 +997,32 @@ val lisp_parse(val source_in, val error_stream, val error_return_val)
   val name = if3(stringp(source),
                  format(nil, lit("expr --> ~a"), source, nao),
                  stream_get_prop(input_stream, name_k));
-  val save_stream = std_error;
   val stream = make_catenated_stream(list(secret_token_stream, input_stream, nao));
+  val saved_dyn = dyn_env;
   parser_t parser;
 
+  dyn_env = make_env(nil, nil, dyn_env);
+
   error_stream = default_bool_arg(error_stream);
-  std_error = if3(error_stream == t, std_output, or2(error_stream, std_null));
+  error_stream = if3(error_stream == t, std_output, or2(error_stream, std_null));
+  class_check (error_stream, stream_s);
+
+  env_vbind(dyn_env, stderr_s, error_stream);
+
   {
     int gc = gc_state(0);
     name = if3(std_error != std_null, name, lit(""));
     parse(stream, name, &parser);
     gc_state(gc);
   }
-  std_error = save_stream;
+
+  dyn_env = saved_dyn;
 
   if (parser.errors) {
     if (missingp(error_return_val))
       uw_throwf(syntax_error_s, lit("read: syntax error"), nao);
     return error_return_val;
   }
+
   return parser.syntax_tree;
 }