Реализация на оператор за намиране на най-малка неподвижна точка

triffon · Oct 23, 2019 · f85cd68 · f85cd68
1 parent b24ce4a
commit f85cd68
Showing 1 changed file with 9 additions and 1 deletion.
diff --git a/lectures/scheme/highorder.scm b/lectures/scheme/highorder.scm
@@ -98,4 +98,12 @@
 (define (gamma f)
   (lambda (n)
     (if (= n 0) 1 (* n (f (- n 1))))))
-(define (fact n) ((gamma fact) n))
+(define (fact n) ((gamma fact) n))
+
+(define (fact n) (((repeated gamma (+ n 1)) 'empty) n))
+
+(define (Y g)
+  (define (gamma-inf me) (lambda (n) ((g (me me)) n)))
+  (gamma-inf gamma-inf))
+
+(define fact (Y gamma))