A-M baby

Task/Jensens-Device/Racket/jensens-device-1.rkt

@@ -0,0 +1,18 @@
+#lang algol60
+begin
+   integer i;
+   real procedure sum (i, lo, hi, term);
+      value lo, hi;
+      integer i, lo, hi;
+      real term;
+      comment term is passed by-name, and so is i;
+   begin
+      real temp;
+      temp := 0;
+      for i := lo step 1 until hi do
+         temp := temp + term;
+      sum := temp
+   end;
+   comment note the correspondence between the mathematical notation and the call to sum;
+   printnln (sum (i, 1, 100, 1/i))
+end

Task/Jensens-Device/Racket/jensens-device-2.rkt

@@ -0,0 +1,4 @@
+#lang racket/base
+(define (sum lo hi f)
+  (for/sum ([i (in-range lo (add1 hi))]) (f i)))
+(sum 1 100 (λ(i) (/ 1.0 i)))