Merge branch 'master' of https://github.com/Make-School-Courses/MOB-2.4-Advanced-Architectural-Patterns-in-iOS

Author: amelinagzz

Lessons/09-Functional-ProgrammingPt.1/assignments/activity.md

@@ -1,7 +1,12 @@
 
 ## In Class Activity
 
-### Individually
+### Individually or In a team create a playground or Repl.it to work on the following:
+
+#### Resources:
+- [map documentation](https://developer.apple.com/documentation/swift/array/3017522-map)
+- [filter documentation](https://developer.apple.com/documentation/swift/sequence/3018365-filter)
+- [reduce documentation](https://developer.apple.com/documentation/swift/array/2298686-reduce)
 
 1. Here is an imperative version of a function called `doubleIt` that takes an array of numbers and returns a new array after doubling every item in the initial array:
 
@@ -19,8 +24,6 @@ func doubleIt(inputArray: Array<Int>) {
 doubleIt(inputArray: [1,2,3]) // [2,4,6]
 ```
 
-**TODO:**
-
 Code the declarative (FP) version of `doubleIt`so that it achieves the same result as the code above by using the `map` function instead of the `for loop`
 
 <!--
@@ -38,11 +41,11 @@ doubleIt(inputArray: [1,2,3]) // [2,4,6]
 
 2. Suppose we have an array containing strings representing the contents of a directory:
 
-let exampleFiles = ["README.md", "HelloWorld.swift", "FlappyBird.swift"]
+`let exampleFiles = ["README.md", "HelloWorld.swift", "FlappyBird.swift"]`
 
-Now suppose we want an array of all the .swift files. This is easy to compute with a simple loop. Use the HOF filter.
+Now suppose we want an array of all the .swift files. This is easy to compute with a simple loop. Use the HOF `filter`.
 
-3. Define a function that sums all the integers in an array.
+3. Define a function that sums all the integers in an array. Use `reduce`
 
 4. Suppose we have the following struct, consisting of a city’s name and population (measured in thousands of inhabitants):
 
@@ -71,3 +74,6 @@ let cities = [paris, madrid, amsterdam, berlin]
 ```
 
 Print a list of cities with at least one million inhabitants, together with their total populations.
+
+
+*From: Chris Eidhof. “Functional Swift.” Apple Books*