Merge pull request #131 from iamvery/list-koans

List koans

lib/koans/07_lists.ex

@@ -20,11 +20,11 @@ defmodule Lists do
   end
 
   koan "Evolution can have different forms" do
-    assert List.delete([1, 2, 2, 3], 2) == ___
+    assert List.delete([:a, :b, :c], :b) == ___
   end
 
   koan "Precision is also valued" do
-    assert List.delete_at([1, 2, 3], 1) == ___
+    assert List.delete_at([:a, :b, :c], 2) == ___
   end
 
   koan "Replication is also possible" do
@@ -63,6 +63,10 @@ defmodule Lists do
     assert List.wrap("value") == ___
   end
 
+  koan "Wrapping nothing produces a list of nothing" do
+    assert List.wrap(nil) == ___
+  end
+
   koan "When there is already a list do not wrap it again" do
     assert List.wrap(["value"]) == ___
   end

test/koans/lists_koans_test.exs

@@ -7,8 +7,8 @@ defmodule ListsTests do
                3,
                [1, 2, :a, "b"],
                [1,2],
-               [1,2,3],
+               [:a, :c],
-               [1,3],
+               [:a, :b],
                ["life", "life", "life"],
                [1, 2, 3, 4, 5],
                [1, 4, 2, 3],
@@ -18,6 +18,7 @@ defmodule ListsTests do
                [1, 2, 3, 4],
                {1, 2, 3},
                ["value"],
+               [],
                ["value"],
                ]