From 0c1babb6c5a289e13105b6e99fd2896ffdc4f944 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Tue, 22 Oct 2013 00:19:43 +0900
Subject: [PATCH] add pic_reverse

---
 include/picrin/pair.h |  2 ++
 src/codegen.c         | 10 +---------
 src/pair.c            | 11 +++++++++++
 3 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/include/picrin/pair.h b/include/picrin/pair.h
index 2d5a02b2..c44aef8e 100644
--- a/include/picrin/pair.h
+++ b/include/picrin/pair.h
@@ -8,6 +8,8 @@ pic_value pic_cdr(pic_state *, pic_value);
 bool pic_list_p(pic_state *, pic_value);
 pic_value pic_list(pic_state *, size_t, ...);
 
+pic_value pic_reverse(pic_state *, pic_value);
+
 pic_value pic_assq(pic_state *, pic_value key, pic_value assoc);
 pic_value pic_acons(pic_state *, pic_value key, pic_value val, pic_value assoc);
 
diff --git a/src/codegen.c b/src/codegen.c
index d9b36e43..1d26dab6 100644
--- a/src/codegen.c
+++ b/src/codegen.c
@@ -389,21 +389,13 @@ pic_gen(pic_state *pic, struct pic_irep *irep, pic_value obj, struct pic_env *en
   }
 }
 
-static pic_value
-reverse(pic_state *pic, pic_value list, pic_value acc)
-{
-  if (pic_nil_p(list))
-    return acc;
-  return reverse(pic, pic_cdr(pic, list), pic_cons(pic, pic_car(pic, list), acc));
-}
-
 static void
 pic_gen_call(pic_state *pic, struct pic_irep *irep, pic_value obj, struct pic_env *env)
 {
   pic_value seq;
   int i = 0;
 
-  seq = reverse(pic, obj, pic_nil_value());
+  seq = pic_reverse(pic, obj);
   for (; ! pic_nil_p(seq); seq = pic_cdr(pic, seq)) {
     pic_value v;
 
diff --git a/src/pair.c b/src/pair.c
index 63fa1e40..9325cf22 100644
--- a/src/pair.c
+++ b/src/pair.c
@@ -48,6 +48,17 @@ pic_list_p(pic_state *pic, pic_value obj)
   return pic_nil_p(obj);
 }
 
+pic_value
+pic_reverse(pic_state *pic, pic_value list)
+{
+  pic_value v, acc = pic_nil_value();
+
+  for (v = list; ! pic_nil_p(v); v = pic_cdr(pic ,v)) {
+    acc = pic_cons(pic, pic_car(pic, v), acc);
+  }
+  return acc;
+}
+
 pic_value
 pic_assq(pic_state *pic, pic_value key, pic_value assoc)
 {