From 1e4bc0411214f1013b8873872b8c832eaf80915c Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Mon, 21 Jul 2014 22:51:33 +0900
Subject: [PATCH] rewrite list<->vector converters in c

---
 piclib/picrin/macro.scm | 18 -----------------
 piclib/prelude.scm      | 41 ++------------------------------------
 src/vector.c            | 44 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 46 insertions(+), 57 deletions(-)

diff --git a/piclib/picrin/macro.scm b/piclib/picrin/macro.scm
index 2f9fe7e0..5682d8ca 100644
--- a/piclib/picrin/macro.scm
+++ b/piclib/picrin/macro.scm
@@ -6,24 +6,6 @@
 
   ;; assumes no derived expressions are provided yet
 
-  (define (list->vector list)
-    (define vector (make-vector (length list)))
-    (define (go list i)
-      (if (null? list)
-          vector
-          (begin
-            (vector-set! vector i (car list))
-            (go (cdr list) (+ i 1)))))
-    (go list 0))
-
-  (define (vector->list vector)
-    (define (go i)
-      (if (= i (vector-length vector))
-          '()
-          (cons (vector-ref vector i)
-                (go (+ i 1)))))
-    (go 0))
-
   (define (walk proc expr)
     "walk on symbols"
     (if (null? expr)
diff --git a/piclib/prelude.scm b/piclib/prelude.scm
index 7049c2f0..2f5f9dae 100644
--- a/piclib/prelude.scm
+++ b/piclib/prelude.scm
@@ -91,22 +91,6 @@
                        (r 'it)
                        (cons (r 'or) (cdr exprs))))))))))
 
-  (define (list->vector list)
-    (let ((vector (make-vector (length list))))
-      (let loop ((list list) (i 0))
-        (if (null? list)
-            vector
-            (begin
-              (vector-set! vector i (car list))
-              (loop (cdr list) (+ i 1)))))))
-
-  (define (vector->list vector)
-    (let ((length (vector-length vector)))
-      (let loop ((list '()) (i 0))
-        (if (= i length)
-            (reverse list)
-            (loop (cons (vector-ref vector i) list) (+ i 1))))))
-
   (define-syntax quasiquote
     (ir-macro-transformer
      (lambda (form inject compare)
@@ -714,27 +698,7 @@
 ;;; 6.8. Vector
 
 (define (vector . objs)
-  (let ((len (length objs)))
-    (let ((v (make-vector len)))
-      (do ((i 0 (+ i 1))
-	   (l objs (cdr l)))
-	  ((= i len)
-	   v)
-	(vector-set! v i (car l))))))
-
-(define (vector->list vector . opts)
-  (let ((start (if (pair? opts) (car opts) 0))
-	(end (if (>= (length opts) 2)
-		 (cadr opts)
-		 (vector-length vector))))
-    (do ((i start (+ i 1))
-	 (res '()))
-	((= i end)
-	 (reverse res))
-      (set! res (cons (vector-ref vector i) res)))))
-
-(define (list->vector list)
-  (apply vector list))
+  (list->vector objs))
 
 (define (vector-copy! to at from . opts)
   (let* ((start (if (pair? opts) (car opts) 0))
@@ -785,8 +749,7 @@
 (define (string->vector . args)
   (list->vector (apply string->list args)))
 
-(export vector vector->list list->vector
-        vector-copy! vector-copy
+(export vector vector-copy! vector-copy
         vector-append vector-fill!
         vector->string string->vector)
 
diff --git a/src/vector.c b/src/vector.c
index 917f0878..1315753f 100644
--- a/src/vector.c
+++ b/src/vector.c
@@ -119,6 +119,48 @@ pic_vec_vector_set(pic_state *pic)
   return pic_none_value();
 }
 
+static pic_value
+pic_vec_list_to_vector(pic_state *pic)
+{
+  struct pic_vector *vec;
+  pic_value list, e, *data;
+
+  pic_get_args(pic, "o", &list);
+
+  vec = pic_vec_new(pic, pic_length(pic, list));
+
+  data = vec->data;
+
+  pic_for_each (e, list) {
+    *data++ = e;
+  }
+  return pic_obj_value(vec);
+}
+
+static pic_value
+pic_vec_vector_to_list(pic_state *pic)
+{
+  struct pic_vector *vec;
+  pic_value list;
+  int n, start, end, i;
+
+  n = pic_get_args(pic, "v|ii", &vec, &start, &end);
+
+  switch (n) {
+  case 1:
+    start = 0;
+  case 2:
+    end = vec->len;
+  }
+
+  list = pic_nil_value();
+
+  for (i = start; i < end; ++i) {
+    pic_push(pic, vec->data[i], list);
+  }
+  return pic_reverse(pic, list);
+}
+
 void
 pic_init_vector(pic_state *pic)
 {
@@ -127,4 +169,6 @@ pic_init_vector(pic_state *pic)
   pic_defun(pic, "vector-length", pic_vec_vector_length);
   pic_defun(pic, "vector-ref", pic_vec_vector_ref);
   pic_defun(pic, "vector-set!", pic_vec_vector_set);
+  pic_defun(pic, "list->vector", pic_vec_list_to_vector);
+  pic_defun(pic, "vector->list", pic_vec_vector_to_list);
 }