Edited source code for Ch1

Author: Bob Lee

course/swift-fundamentals/class-struct-difference.md

@@ -152,7 +152,7 @@ To learn more about cons of Object Oriented Programming, you may read the beginn
 ### Source Code
 [1008_class_struct_difference.playground]
 
-[1008_class_struct_difference.playground]:https://www.dropbox.com/sh/der2imu4z41c7nr/AAAaLyZhh4jJLe-_oQFPFGmxa?dl=0
+[1008_class_struct_difference.playground]:https://www.dropbox.com/sh/8996uqzt2334y4p/AACCyGZNVNoJC-7MzHo0ywn8a?dl=0
 
 
 ## Conclusion

course/swift-fundamentals/extension.md

@@ -100,7 +100,7 @@ As mentioned, `extension` allows developers to implement all kinds of features.
 
 
 ### Source Code
-[1010_extension.playground](https://www.dropbox.com/sh/nom0467cql4yt1g/AAB4UmnnlpCE1c36qbXZKAiOa?dl=0)
+[1010_extension.playground]https://www.dropbox.com/sh/dq1288vcb77fzk6/AADgJhq0idPwIFTOTbysAxW7a?dl=0)
 
 ## Conclusion
 You've learned the meaning of `self`.  I use `extension` to modularize view controller to prevent MVC, a.k.a, Massive View Controller.

course/swift-fundamentals/generics.md

@@ -192,7 +192,7 @@ addLOLClassOnly(array: [1, 2, 3, 4, 5]) // Error
 [Intro to Generics in Swift with Bob](https://medium.com/ios-geek-community/intro-to-generics-in-swift-with-bob-df58118a5001#.fkmmjqnwd)
 
 ### Source Code
-[1006_generics.playground](https://www.dropbox.com/sh/wuf65widfors50d/AABCJF-aojTJLPGdA79Vc78Ma?dl=0)
+[1006_generics.playground](https://www.dropbox.com/sh/p8i8134nmljh0js/AADR4Gi-RyEfyc_AwtA9H4aEa?dl=0)
 
 ## Conclusion
 You now understand how to maintain yourself dry through generic functions and structs. In later chapters, you will more about advanced generics along with `enums` and `protocols`. If you wish to review generic the syntax, I recommend you to watch the lecture again or refer to the article I've attached.

course/swift-fundamentals/guard-defer-statement.md

@@ -217,7 +217,7 @@ for i in 1...3 {
   - Any code you want to explicitly inform your team without requiring them to read the entire function
 
 ### Source Code
-[1003_guard_defer_statement.playground](https://www.dropbox.com/sh/n0kb3mv5unyhj5w/AADzn2E55lnMbi2d39pVjS6aa?dl=0)
+[1003_guard_defer_statement.playground](https://www.dropbox.com/sh/s3zztv3o6h3xv6v/AABWT2Le9T9SXJegSq9pr19pa?dl=0)
 
 ## Conclusion
 In this lesson, you've learned the power of `guard` over typical `else-if`.  First, it provides an early exit. Second, no one has to read the entire function to spot the error messages. You use a `guard` statement not just to please yourself, but for the sake of your teammates' falling hair when he/she reads your code. Keep guarding, everyone. Don't defer your learning, however.

course/swift-fundamentals/intro-error-handling.md

@@ -144,7 +144,7 @@ let myDopeNewCourse = try! Course(name: "") // ☠️
 ```
 
 ### Source Code
-[1004_intro_error_handling.playground](https://www.dropbox.com/sh/kiib6lgy1xa7lww/AAANnWweDDT_KB4-hFJEB9taa?dl=0)
+[1004_intro_error_handling.playground](https://www.dropbox.com/sh/9ywof00ryj3s12k/AAAcowGDCfFYCxQW_J5hhidYa?dl=0)
 
 ### Resources
 [Intro to Error Handling by Bob the Developer](https://goo.gl/EaepCa)

course/swift-fundamentals/intro-operators.md

@@ -100,7 +100,7 @@ finalUserAge = age ?? defaultAge // finalUserAge is 20
 The above states that if `age` contains `nil`, use `defaultAge` instead. Nice and simple.
 
 ### Source Code
-[1011_operators.playground](https://www.dropbox.com/sh/1cz94ffju3e8smz/AABbbdMDL5Ch1-8T4ZHlPlvFa?dl=0)
+[1011_operators.playground](https://www.dropbox.com/sh/pbsgi6bt9p35k9k/AADx8qk44wOpMC5hgmd2DYrna?dl=0)
 
 ## Conclusion
 You've only scratched the surface. In Chapter 8, you will learn how to create your own operators. I know you are excited. Stay consistent and you will get there, hopefully soon.

course/swift-fundamentals/optional-chaining.md

@@ -78,7 +78,7 @@ let NYCResident = NYCApartment.human!.name // Error: No value for human
 ```
 
 ### Source Code
-[1002_optional_chainings.playground](https://www.dropbox.com/sh/t809vje5icodnvz/AACWWIxjan6RlEfvgCuT87uVa?dl=0)
+[1002_optional_chainings.playground](https://www.dropbox.com/sh/czde6dm36navhtj/AABVk37REgAS4eZL8WTuJs7Ga?dl=0)
 
 ### Resources
 My Favorite Xcode Shortcuts [Part 1], [Part 2], [Part 3]

course/swift-fundamentals/optionals.md

@@ -116,7 +116,7 @@ if let normalImage = imageFromFaceBook {
 Now `normalImage` contains a normal type of `String`. You may use the `normalImage` constant within the `if` block. On the contrary, if `imageFromFaceBook` contains `nil`, Swift executes the `else` block instead.
 
 ### Source Code
-[1001_optionals.playground](https://www.dropbox.com/sh/0u7dqz6e84zst9y/AAA90TqRvoX7Gf4oCpCBrEPya?dl=0)
+[1001_optionals.playground](https://www.dropbox.com/sh/wmnw7tpa16v8emo/AADjm-MP8lZOKZM0P6kPA4rea?dl=0)
 
 ### Resources {#google_slide}
 <iframe src="https://docs.google.com/presentation/d/1DDhLcBX6kBheVXlQNxMCrJp_OP0mXC82NgJHCPnW-OY/embed?start=false&loop=false&delayms=3000" frameborder="0" width="100%" height="460" allowfullscreen="true" mozallowfullscreen="true" webkitallowfullscreen="true"></iframe>

course/swift-fundamentals/set-tuple.md

@@ -227,7 +227,7 @@ for (index, value) in shoppingList.enumerated() {
 ```
 
 ### Source Code
-[1009_set_tuple.playground](https://www.dropbox.com/sh/w3b55cig44dkn18/AADfa-mpPqoWgDUOrhn02_goa?dl=0)
+[1009_set_tuple.playground](https://www.dropbox.com/sh/u0ltcnxjiao4s9s/AAAAAZZdGxSUhUCd2nUCpKwFa?dl=0)
 
 ### Reference
 [Swift API Design Guidelines](https://swift.org/documentation/api-design-guidelines/)

course/swift-fundamentals/subscripts.md

@@ -89,7 +89,7 @@ No context means = ☠️
  2. Anything has to do with pairs and collection types
 
 ### Source Code
-[1107_subscripts.playground](https://www.dropbox.com/sh/mrrmaocche40bye/AADQlKE45soQzf48J1MEK1V3a?dl=0)
+[1107_subscripts.playground](https://www.dropbox.com/sh/0i0ut11pvx3wfux/AAARAUiJ3AGd7gn3p1JfxtLZa?dl=0)
 
 
 ## Conclusion