3 files changed, 10 insertions, 0 deletions

diff --git a/builtin.cpp b/builtin.cpp
index 94fcd9b..a8091ba 100644
--- a/builtin.cpp
+++ b/builtin.cpp
@@ -1028,6 +1028,7 @@ BUILTIN_PROC_DEF(num_lt) {
         throw TokenError("a number", RUN_ERR_WRONG_TYPE);
 
     NumObj *last = static_cast<NumObj*>(args->car), *opr;
+    args = TO_PAIR(args->cdr);
     for (; args != empty_list; args = TO_PAIR(args->cdr), last = opr)
     {
         if (!args->car->is_num_obj())        // not a number
@@ -1052,6 +1053,7 @@ BUILTIN_PROC_DEF(num_gt) {
         throw TokenError("a number", RUN_ERR_WRONG_TYPE);
 
     NumObj *last = static_cast<NumObj*>(args->car), *opr;
+    args = TO_PAIR(args->cdr);
     for (; args != empty_list; args = TO_PAIR(args->cdr), last = opr)
     {
         if (!args->car->is_num_obj())        // not a number
@@ -1076,6 +1078,7 @@ BUILTIN_PROC_DEF(num_eq) {
         throw TokenError("a number", RUN_ERR_WRONG_TYPE);
 
     NumObj *last = static_cast<NumObj*>(args->car), *opr;
+    args = TO_PAIR(args->cdr);
     for (; args != empty_list; args = TO_PAIR(args->cdr), last = opr)
     {
         if (!args->car->is_num_obj())        // not a number
@@ -1417,6 +1420,11 @@ do { \
     return new BoolObj(true);
 }
 
+BUILTIN_PROC_DEF(is_number) {
+    ARGS_EXACTLY_ONE;
+    return new BoolObj(args->car->is_num_obj());
+}
+
 BUILTIN_PROC_DEF(display) {
     ARGS_EXACTLY_ONE;
     printf("%s\n", args->car->ext_repr().c_str());
diff --git a/builtin.h b/builtin.h
index b3aef77..7b2c6d1 100644
--- a/builtin.h
+++ b/builtin.h
@@ -262,6 +262,7 @@ BUILTIN_PROC_DEF(num_eq);
 
 BUILTIN_PROC_DEF(num_is_exact);
 BUILTIN_PROC_DEF(num_is_inexact);
+BUILTIN_PROC_DEF(is_number);
 
 BUILTIN_PROC_DEF(bool_not);
 BUILTIN_PROC_DEF(is_boolean);
diff --git a/eval.cpp b/eval.cpp
index 1e78a8e..323c4c9 100644
--- a/eval.cpp
+++ b/eval.cpp
@@ -34,6 +34,7 @@ void Evaluator::add_builtin_routines() {
 
     ADD_BUILTIN_PROC("exact?", num_is_exact);
     ADD_BUILTIN_PROC("inexact?", num_is_inexact);
+    ADD_BUILTIN_PROC("number?", is_number);
 
     ADD_BUILTIN_PROC("not", bool_not);
     ADD_BUILTIN_PROC("boolean?", is_boolean);