September 2017 Update

Task/Ackermann-function/Elena/ackermann-function.elena

@@ -1,26 +1,29 @@
-#define system.
-#define extensions.
+import extensions.
 
-// --- Ackermann function ---
-
-#symbol ackermann = (:m:n)
+ackermann = (:m:n)
 [
+    if((n < 0)||(m < 0))
+    [
+        InvalidArgumentException new; raise
+    ].
+
     m =>
-       0 ? [ n + 1 ]
-       > 0 ? [
-              n => 0 ? [ ackermann eval:(m - 1):1 ]
-                       > 0 ? [ ackermann eval:(m - 1):(ackermann eval:m:(n-1)) ]
+       0 [ ^n + 1 ];
+       ! [
+              n =>
+                0 [ ^ackermann eval(m - 1,1) ];
+                ! [ ^ackermann eval(m - 1,ackermann eval(m,n-1)) ]
            ]
 ].
 
-#symbol program =
+program =
 [
-    0 to:3 &doEach: (:i)
+    0 to:3 do(:i)
     [
-        0 to:5 &doEach: (:j)
+        0 to:5 do(:j)
         [
-            console writeLine:"A(":i:",":j:")=":(ackermann eval:i:j).
-        ].
+            console printLine("A(",i,",",j,")=",ackermann eval(i,j))
+        ]
     ].
 
     console readChar.