diff -r c5f89ee12d25 -r 3a9acfc6106b marking3/knight1_test4.scala
--- a/marking3/knight1_test4.scala	Tue Feb 04 11:20:31 2020 +0000
+++ b/marking3/knight1_test4.scala	Tue Feb 04 14:15:42 2020 +0000
@@ -1,5 +1,7 @@
+import CW8a._
 
-val f = (x:(Int, Int)) => if (x._1 > 3) Some(List(x)) else None
 
-assert(first(List((1,0),(2,0),(3,0),(4,0)), f) == Some(List((4,0))))
-assert(first(List((1,0),(2,0),(3,0)), f) == None)
+val f_urban = (x:(Int, Int)) => if (x._1 > 3) Some(List(x)) else None
+
+assert(first(List((1,0),(2,0),(3,0),(4,0)), f_urban) == Some(List((4,0))))
+assert(first(List((1,0),(2,0),(3,0)), f_urban) == None)