unoidl2

commit 0cc11334c93bfb095fb88fe06d7f808888d9c89f
parent c61c8326110cfe3639af0f60b0f946ef19a0b443
Author: Tomas Hlavaty <tom@logand.com>
Date:   Tue, 13 Mar 2012 23:25:26 +0100

better intern1

Diffstat:
M
unoidl2.c
 | 
23
+++++++++++------------

1 file changed, 11 insertions(+), 12 deletions(-)
diff --git a/unoidl2.c b/unoidl2.c
@@ -64,21 +64,19 @@ Any cons(Any car, Any cdr) {
   return x;
 }
 
-static Any root1 = NULL;
+static Any root1;
+static Any intern1_k;
 
 Any intern1(char *x) {
-  if(x) {
-    Any root = root1;
-    while(*x) {
-      Any c = mkchara(*x++); // TODO no consing
-      Any root2 = find(c, cdr(root), equal, caar);
-      if(NIL == root2)
-        root->u.c.cdr = cons(root2 = list1(cons(c, root)), cdr(root));
-      root = root2;
-    }
-    return root;
+  Any p = root1;
+  for(; *x; x++) {
+    intern1_k->u.chara = *x;
+    Any r = find(intern1_k, cdr(p), equal, caar);
+    if(NIL == r)
+      p->u.c.cdr = cons(r = list1(cons(mkchara(*x), p)), cdr(p));
+    p = r;
   }
-  return NIL;
+  return p;
 }
 
 Any mk(Kind kind, char *token) {
@@ -260,6 +258,7 @@ void init() {
   NIL->u.c.car = NIL;
   NIL->u.c.cdr = NIL;
   root1 = list1(NIL);
+  intern1_k = mkchara(0);
   T = xalloc();
   T->tag = TOKEN;
   T->u.t.kind = 0;