Homework 3

elm-todo/Todo.elm

@@ -45,7 +45,6 @@ type alias Model =
 type alias Entry =
     { description : String
     , completed : Bool
-    , editing : Bool
     , id : Int
     }
 
@@ -62,7 +61,6 @@ newEntry : String -> Int -> Entry
 newEntry desc id =
     { description = desc
     , completed = False
-    , editing = False
     , id = id
     }
 
@@ -76,7 +74,6 @@ to them.
 -}
 type Msg
     = UpdateNewEntryField String
-    | EditingEntry Int Bool
     | UpdateEntry Int String
     | Add
     | Delete Int
@@ -102,19 +99,6 @@ update msg model =
         UpdateNewEntryField str ->
             { model | newEntryField = str }
 
-        EditingEntry id isEditing ->
-            let
-                updateEntry t =
-                    if t.id == id then
-                        { t | editing = isEditing }
-                    else
-                        t
-
-                focus =
-                    Dom.focus ("todo-" ++ toString id)
-            in
-                { model | entries = List.map updateEntry model.entries }
-
         UpdateEntry id task ->
             let
                 updateEntry t =
@@ -229,7 +213,7 @@ viewKeyedEntry todo =
 viewEntry : Entry -> Html Msg
 viewEntry todo =
     li
-        [ classList [ ( "completed", todo.completed ), ( "editing", todo.editing ) ] ]
+        [ classList [ ( "completed", todo.completed )] ]
         [ div
             [ class "view" ]
             [ input
@@ -240,8 +224,8 @@ viewEntry todo =
                 ]
                 []
             , label
-                [ onDoubleClick (EditingEntry todo.id True) ]
-                [ text todo.description ]
+                []
+                [ text todo.description]
             , button
                 [ class "destroy"
                 , onClick (Delete todo.id)
@@ -253,9 +237,6 @@ viewEntry todo =
             , value todo.description
             , name "title"
             , id ("todo-" ++ toString todo.id)
-            , onInput (UpdateEntry todo.id)
-            , onBlur (EditingEntry todo.id False)
-            , onEnter (EditingEntry todo.id False)
             ]
             []
         ]
@@ -313,8 +294,7 @@ viewControlsClear entriesCompleted =
 infoFooter : Html msg
 infoFooter =
     footer [ class "info" ]
-        [ p [] [ text "Double-click to edit a todo" ]
-        , p []
+        [ p []
             [ text "Written by "
             , a [ href "https://github.com/evancz" ] [ text "Evan Czaplicki" ]
             ]

ruby-todo/lib/engine.rb

@@ -5,8 +5,13 @@ def self.run(*args)
 
   def self.run_with_history(model, messages)
     messages.map do |msg|
-      msg.apply_to(model)
-      model
+      model = msg.apply_to(model)
+
     end
+
+    # [msg1, msg2, msg3]
+    # [model with msg1, model with msg2, model with msg3]
+    # [model with msg1, model with msg1, msg2, model with msg1, msg2, msg3]
+
   end
 end

ruby-todo/lib/messages.rb

@@ -2,13 +2,13 @@ module Msg
 
   class Add
     def apply_to(model)
+      newEntries = model.entries.clone
+
       unless model.new_entry_field.blank?
-        model.entries << Entry.new(
-          description: model.new_entry_field,
-          id: model.next_id)
+        newEntries << Entry.new(description: model.new_entry_field,id: model.next_id)
       end
-      model.next_id += 1
-      model.new_entry_field = ""
+
+      Model.new(new_entry_field: "", entries: newEntries, next_id: model.next_id + 1 )
     end
   end
 
@@ -20,7 +20,7 @@ def initialize(str)
     attr_reader :str 
 
     def apply_to(model)
-      model.new_entry_field = str
+      Model.new(new_entry_field: str, entries: model.entries.clone, next_id: model.next_id )
     end
   end
 
@@ -30,13 +30,18 @@ def initialize(id, is_completed)
     end
 
     attr_reader :id, :is_completed 
-
     def apply_to(model)
-      model.entries.each do |entry|
+      # [1,2,3,4].map do |digit|
+      #   digit + 1
+      # end == [2,3,4,5]
+
+      Model.new(new_entry_field: model.new_entry_field, next_id: model.next_id, entries: model.entries.clone.map do |entry|
         if entry.id == id
-          entry.completed = is_completed
+          entry = Entry.new(id: id, description: entry.description, completed: is_completed)
         end
+        entry
       end
+      )
     end
   end
 
@@ -46,15 +51,15 @@ def initialize(id)
     end
 
     attr_reader :id 
-
     def apply_to(model)
-      model.entries.reject! { |e| e.id == id }
+      Model.new(new_entry_field: model.new_entry_field, next_id: model.next_id, entries: model.entries.clone.reject! { |e| e.id == id }
+        )
     end
   end
 
   class DeleteAllCompleted
     def apply_to(model)
-      model.entries.reject!(&:completed)
+      Model.new(new_entry_field: model.new_entry_field, next_id: model.next_id, entries: model.entries.clone.reject!(&:completed))
     end
   end
 

ruby-todo/lib/model.rb

@@ -5,7 +5,7 @@ def initialize(entries: [], new_entry_field: "", next_id: nil)
       (entries.lazy.map(&:id).max || -1) + 1
   end
 
-  attr_accessor :entries, :new_entry_field, :next_id
+  attr_reader :entries, :new_entry_field, :next_id
 
   def ==(other)
     !other.nil? &&
@@ -20,7 +20,7 @@ def initialize(id:, description:, completed: false)
     @description, @id, @completed = description, id, completed
   end
 
-  attr_accessor :description, :completed, :id
+  attr_reader :description, :completed, :id
 
   def ==(other)
     !other.nil? &&

ruby-todo/test/todo_test.rb

@@ -27,11 +27,17 @@
 
   describe Msg::Add do
     it "appends a new entry" do
+
+      # print model.inspect
+      # print "\n\n\n"
+
       new_model = Engine.run(model, [
         Msg::UpdateNewEntryField.new("hop on one foot"),
         Msg::Add.new
       ])
 
+      # print new_model.inspect
+      # print "\n\n\n"
       assert_equal 3, new_model.entries.size
       new_entry = new_model.entries.last
       assert_equal 12, new_entry.id
@@ -91,7 +97,7 @@
   end
 
   it "supports time travel" do
-    skip "Mutable model does not support time travel"
+    # skip "Mutable model does not support time travel"
 
     actual_history = Engine.run_with_history(Model.new, [
       Msg::UpdateNewEntryField.new("go forward in time"),
@@ -104,7 +110,7 @@
       Msg::UpdateNewEntryField.new("go backward in time"),
       Msg::Add.new,
       Msg::Check.new(0, true),
-      Msg::Check.new(3, true),
+      Msg::Check.new(3, true), 
       Msg::Check.new(3, false),
       Msg::DeleteAllCompleted.new
     ])

swift-todo/Sources/Todo/Engine.swift

@@ -13,9 +13,12 @@ struct Engine {
     }
 
     static func runWithHistory(on model: Model, applying messages: [Message]) -> [Model] {
+        var oldModel = model
         return messages.map { message in
-          message.apply(to: model)
-          return model
+            oldModel = message.apply(to: oldModel)
+            return oldModel
         }
     }
 }
+
+

swift-todo/Sources/Todo/Message.swift

@@ -7,37 +7,55 @@
 
 import Foundation
 
+//array = [a,b,c]
+//
+//map (function)
+//array: a -> function(a) -> x
+//
+//
+//function = { y in
+//
+//    return x
+//}
+
 enum Message {
     case add
     case updateNewEntryField(String)
     case check(Int, Bool)
     case delete(Int)
     case deleteAllCompleted
 
-    func apply(to model: Model) {
+    func apply(to model: Model) -> Model {
+        var mutableModel = model
+
         switch(self) {
             case .add:
                 if !model.newEntryField.isBlank() {
-                    model.entries.append(Entry(id: model.nextID, description: model.newEntryField))
+                    mutableModel.entries.append(Entry(id: model.nextID, description: model.newEntryField))
                 }
-                model.nextID += 1
-                model.newEntryField = ""
+
+                mutableModel.nextID += 1
+                mutableModel.newEntryField = ""
 
             case .updateNewEntryField(let str):
-                model.newEntryField = str
+                mutableModel.newEntryField = str
 
             case .check(let id, let isCompleted):
-                for entry in model.entries {
+                mutableModel.entries = mutableModel.entries.map { entry in
+                    var mutableEntry = entry
                     if(entry.id == id) {
-                        entry.completed = isCompleted
+                        mutableEntry.id = id
+                        mutableEntry.completed = isCompleted
                     }
+                    return mutableEntry
                 }
 
             case .delete(let id):
-                model.entries.remove { $0.id == id }
+                mutableModel.entries.remove { $0.id == id }
 
             case .deleteAllCompleted:
-                model.entries.remove { $0.completed }
+                mutableModel.entries.remove { $0.completed }
         }
+        return mutableModel
     }
 }

swift-todo/Sources/Todo/Model.swift

@@ -1,4 +1,4 @@
-class Model {
+struct Model {
     var entries: [Entry]
     var newEntryField: String
     var nextID: Int
@@ -11,7 +11,7 @@ class Model {
     }
 }
 
-class Entry {
+struct Entry {
     var id: Int
     var description: String
     var completed: Bool

swift-todo/Tests/TodoTests/TodoTests.swift

@@ -77,7 +77,7 @@ class TodoTests: XCTestCase {
          XCTAssertEqual([11], newModel.entries.map { $0.id })
      }
 
-/*
+
      func testTimeTravel() {
         let actualHistory = Engine.runWithHistory(on: Model(), applying: [
              .updateNewEntryField("go forward in time"),
@@ -145,6 +145,6 @@ class TodoTests: XCTestCase {
              XCTAssertEqual(expected, actual, "History mismatch at step \(index)")
          }
     }
-*/
+
 
 }