Anonymous recursion: Difference between revisions

Content added Content deleted

Inline

@@ Line 2,045: / Line 2,045: @@
 {{trans|Common_Lisp}}
+<lang txr>(defmacro recursive ((. parm-init-pairs) . body)
-<lang txr>@(do
+  (let ((hidden-name (gensym "RECURSIVE-")))
-   (defmacro recursive ((. parm-init-pairs) . body)
-     (let ((hidden-name (gensym "RECURSIVE-")))
+    ^(macrolet ((recurse (. args) ^(,',hidden-name ,*args)))
-       ^(macrolet ((recurse (. args) ^(,',hidden-name ,*args)))
+       (labels ((,hidden-name (,*[mapcar first parm-init-pairs]) ,*body))
-          (labels ((,hidden-name (,*[mapcar first parm-init-pairs]) ,*body))
+         (,hidden-name ,*[mapcar second parm-init-pairs])))))
-            (,hidden-name ,*[mapcar second parm-init-pairs])))))
-   (defun fib (number)
+(defun fib (number)
-     (if (< number 0)
+  (if (< number 0)
-       (error "Error. The number entered: ~a is negative" number)
+    (error "Error. The number entered: ~a is negative" number)
-       (recursive ((n number) (a 0) (b 1))
+    (recursive ((n number) (a 0) (b 1))
-         (if (= n 0)
+      (if (= n 0)
-           a
+        a
-           (recurse (- n 1) b (+ a b))))))
+        (recurse (- n 1) b (+ a b))))))
-      (put-line `fib(10) = @(fib 10)`)
+(put-line `fib(10) = @(fib 10)`)
-      (put-line `fib(-1) = @(fib -1)`))</lang>
+(put-line `fib(-1) = @(fib -1)`))</lang>
 {{out}}