From: grue <grue@mail.ru>
Date: Mon, 13 Feb 2006 20:50:52 +0000 (+0000)
Subject: below function
X-Git-Url: https://jxself.org/git/?a=commitdiff_plain;h=f590c554e7d2e0eaf32377427416a29f69a74034;p=lifp.git

below function

darcs-hash:1e09aa5eaf5c8dfd2a366b28780a8331e48aeded
---

diff --git a/if.lisp b/if.lisp
index 881c629..5664a60 100644
--- a/if.lisp
+++ b/if.lisp
@@ -42,7 +42,7 @@
            :abstractobject :name :names :parent :children :flags
            :initflags :add-flags :has :hasnt :-> :give :child
            :ifclass :object :defaction :*meta*
-           :move :rmv :ofclass :among
+           :move :rmv :ofclass :among :below
            :verb :extend-verb :extend-verb-first
            :extend-verb-only :extend-verb-only-first
            :deftoken :string== :matchp :!last!
@@ -744,7 +744,14 @@ word in dictionary, add it."
 (defun notin (obj &rest what)
   "Test whether the object is not in any of other arguments"
   (notany (lambda (x) (eql (parent obj) x)) what))
-   
+
+(defun below (obj1 obj2)
+  "Tests whether obj1 is strictly below obj2 in object structure"
+  (loop for x = obj1 then (parent x)
+        while x
+        when (eql x obj2) do (return t)
+        finally (return nil)))
+
 ;;SECTION 9: Verb functions
 
 (defstruct patternlist value)