X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=scheme.forth.jl.git;a=blobdiff_plain;f=scheme-library.scm;h=62a7aa3513148f2bb39eaed311f2d7fb2d0297c4;hp=b92795dfd03f29005d13aa3ac9eb57e5abadbfb3;hb=82b93d081309895fe1a8e446daad5b8a75896fa3;hpb=7888f570d4b32b447622e25c38a4e78197cc7732

diff --git a/scheme-library.scm b/scheme-library.scm
index b92795d..62a7aa3 100644
--- a/scheme-library.scm
+++ b/scheme-library.scm
@@ -29,11 +29,28 @@
 
 ;; LIBRARY FORMS
 
+(define-macro (while condition . body)
+              `(begin
+                 (define (loop)
+                   (if ,condition
+                     (begin ,@body (loop))))
+                 (loop)))
+
 ;; TESTING
 
 (define-macro (backwards . body)
               (cons 'begin (reverse body)))
 
+(define method '(while (> counter 0)
+                       (display counter) (newline)
+                       (set! counter (- counter 1))))
+
+(define (count)
+  (define counter 10)
+  (while (> counter 0)
+         (display counter) (newline)
+         (set! counter (- counter 1))))
+
 ; Basic iterative summation.  Run this on large numbers to
 ; test garbage collection and tail-call optimization.
 (define (sum n)