From f33d23bca185e2c9d2431d3bca5ab9156b7225b7 Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Sat, 7 Apr 2018 12:18:50 +0200
Subject: [PATCH] core: Add member.

* src/lib.c (member): New function.
* module/mes/scm.mes (member): Remove.
---
 module/mes/scm.mes |  5 -----
 src/lib.c          | 18 ++++++++++++++++++
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/module/mes/scm.mes b/module/mes/scm.mes
index 805b0318..32fc13f6 100644
--- a/module/mes/scm.mes
+++ b/module/mes/scm.mes
@@ -126,11 +126,6 @@
 
 (define memv memq)
 
-(define (member x lst)
-  (if (null? lst) #f
-      (if (equal? x (car lst)) lst
-          (member x (cdr lst)))))
-
 
 ;;; Lists
 (define (make-list n . x)
diff --git a/src/lib.c b/src/lib.c
index 8b46898e..9fb74900 100644
--- a/src/lib.c
+++ b/src/lib.c
@@ -312,3 +312,21 @@ equal2_p (SCM a, SCM b)
     }
   return eq_p (a, b);
 }
+
+SCM
+member (SCM x, SCM a)
+{
+  switch (TYPE (x))
+    {
+    case TCHAR:
+    case TNUMBER:
+    case TKEYWORD:
+    case TSYMBOL:
+    case TSPECIAL:
+      return memq (x, a);
+    default:
+      while (a != cell_nil && equal2_p (x, CAR (a)) != cell_t)
+        a = CDR (a);
+    }
+  return a != cell_nil ? a : cell_f;
+}