Initial data commit

Task/Catamorphism/PureBasic/catamorphism.basic

@@ -0,0 +1,20 @@
+Procedure.i reduce(List l(),op$="+")
+  If FirstElement(l())
+    x=l()
+    While NextElement(l())
+      Select op$
+        Case "+" : x+l()
+        Case "-" : x-l()
+        Case "*" : x*l()
+      EndSelect
+    Wend
+  EndIf
+  ProcedureReturn x
+EndProcedure
+
+NewList fold()
+For i=1 To 5 : AddElement(fold()) : fold()=i : Next
+
+Debug reduce(fold())
+Debug reduce(fold(),"-")
+Debug reduce(fold(),"*")