From 74088d0130db50112533b1bfc09ef1e392b576c5 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Wed, 22 Jan 2014 21:35:13 +0900
Subject: [PATCH] replace list-set! impl with C impl

---
 include/picrin/pair.h |  1 +
 piclib/built-in.scm   |  3 ---
 src/pair.c            | 20 ++++++++++++++++++++
 3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/include/picrin/pair.h b/include/picrin/pair.h
index f2ba887e..20b48dfd 100644
--- a/include/picrin/pair.h
+++ b/include/picrin/pair.h
@@ -32,6 +32,7 @@ pic_value pic_cddr(pic_state *, pic_value);
 
 pic_value pic_list_tail(pic_state *, pic_value ,int);
 pic_value pic_list_ref(pic_state *, pic_value, int);
+void pic_list_set(pic_state *, pic_value, int, pic_value);
 
 #if defined(__cplusplus)
 }
diff --git a/piclib/built-in.scm b/piclib/built-in.scm
index 2e30a7f7..248ab4e2 100644
--- a/piclib/built-in.scm
+++ b/piclib/built-in.scm
@@ -462,9 +462,6 @@
 	  (cons (car args)
 		(make-list (- k 1) (car args))))))
 
-(define (list-set! list k obj)
-  (set-car! (list-tail list k) obj))
-
 (define (list-copy obj)
   (if (null? obj)
       obj
diff --git a/src/pair.c b/src/pair.c
index 8f39df43..3c1e8bbc 100644
--- a/src/pair.c
+++ b/src/pair.c
@@ -213,6 +213,12 @@ pic_list_ref(pic_state *pic, pic_value list, int i)
   return pic_car(pic, pic_list_tail(pic, list, i));
 }
 
+void
+pic_list_set(pic_state *pic, pic_value list, int i, pic_value obj)
+{
+  pic_pair_ptr(pic_list_tail(pic, list, i))->car = obj;
+}
+
 static pic_value
 pic_pair_pair_p(pic_state *pic)
 {
@@ -410,6 +416,19 @@ pic_pair_list_ref(pic_state *pic)
   return pic_list_ref(pic, list, i);
 }
 
+static pic_value
+pic_pair_list_set(pic_state *pic)
+{
+  pic_value list, obj;
+  int i;
+
+  pic_get_args(pic, "oio", &list, &i, &obj);
+
+  pic_list_set(pic, list, i, obj);
+
+  return pic_none_value();
+}
+
 void
 pic_init_pair(pic_state *pic)
 {
@@ -431,4 +450,5 @@ pic_init_pair(pic_state *pic)
   pic_defun(pic, "reverse", pic_pair_reverse);
   pic_defun(pic, "list-tail", pic_pair_list_tail);
   pic_defun(pic, "list-ref", pic_pair_list_ref);
+  pic_defun(pic, "list-set!", pic_pair_list_set);
 }