From 4e895c97d01e4ff98fe68f752c177f71dd1a31bc Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Tue, 22 Jul 2014 09:15:16 +0900
Subject: [PATCH] =?UTF-8?q?rewrite=20symbol=3D=3F=20in=20c?=

---
 piclib/prelude.scm | 13 -------------
 src/symbol.c       | 20 ++++++++++++++++++++
 2 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/piclib/prelude.scm b/piclib/prelude.scm
index 2a9993cc..114bcffa 100644
--- a/piclib/prelude.scm
+++ b/piclib/prelude.scm
@@ -609,19 +609,6 @@
 
 (export member assoc)
 
-;;; 6.5. Symbols
-
-(define (symbol=? . objs)
-  (let ((sym (car objs)))
-    (if (symbol? sym)
-	(every (lambda (x)
-		 (and (symbol? x)
-		      (eq? x sym)))
-	       (cdr objs))
-	#f)))
-
-(export symbol=?)
-
 ;;; 6.6 Characters
 
 (define-macro (define-char-transitive-predicate name op)
diff --git a/src/symbol.c b/src/symbol.c
index 863e41f3..1ebbdc3d 100644
--- a/src/symbol.c
+++ b/src/symbol.c
@@ -77,6 +77,25 @@ pic_symbol_symbol_p(pic_state *pic)
   return pic_bool_value(pic_sym_p(v));
 }
 
+static pic_value
+pic_symbol_symbol_eq_p(pic_state *pic)
+{
+  size_t argc, i;
+  pic_value *argv;
+
+  pic_get_args(pic, "*", &argc, &argv);
+
+  for (i = 0; i < argc; ++i) {
+    if (! pic_sym_p(argv[i])) {
+      return pic_false_value();
+    }
+    if (! pic_eq_p(argv[i], argv[0])) {
+      return pic_false_value();
+    }
+  }
+  return pic_true_value();
+}
+
 static pic_value
 pic_symbol_symbol_to_string(pic_state *pic)
 {
@@ -109,6 +128,7 @@ void
 pic_init_symbol(pic_state *pic)
 {
   pic_defun(pic, "symbol?", pic_symbol_symbol_p);
+  pic_defun(pic, "symbol=?", pic_symbol_symbol_eq_p);
   pic_defun(pic, "symbol->string", pic_symbol_symbol_to_string);
   pic_defun(pic, "string->symbol", pic_symbol_string_to_symbol);
 }