pack.c: simplify

* pack.c (str_associate): remove unnecessary branch.
  the argument must be a plain vanilla string object.

* pack.c (str_associated): use rb_ivar_lookup to give the
  undefined value.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56740 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

pack.c

@@ -116,24 +116,14 @@ static ID id_associated;
 static void
 str_associate(VALUE str, VALUE add)
 {
-    VALUE assoc;
-
-    assoc = rb_attr_get(str, id_associated);
-    if (RB_TYPE_P(assoc, T_ARRAY)) {
-	/* already associated */
-	rb_ary_concat(assoc, add);
-    }
-    else {
-	rb_ivar_set(str, id_associated, add);
-    }
+    /* assert(NIL_P(rb_attr_get(str, id_associated))); */
+    rb_ivar_set(str, id_associated, add);
 }
 
 static VALUE
 str_associated(VALUE str)
 {
-    VALUE assoc = rb_attr_get(str, id_associated);
-    if (NIL_P(assoc)) assoc = Qfalse;
-    return assoc;
+    return rb_ivar_lookup(str, id_associated, Qfalse);
 }
 
 void