1. Build a method that yields members of a collection to a block.
2. Control the return value of a method that uses yield such that it returns a new collection.

You'll be writing your code in lib/my_collect.rb.

You are writing a method that behaves just like the real #collect method. It should take in an argument of a collection, iterate over that collection using a while loop, and execute the code in the block you call it with for each element in the collection (use the yield keyword). It should return the modified collection.

Your #my_collect method, therefore, should not care about the contents of the code block that it is invoked with. For example, let's say we are writing an app to help teachers manage their students. Our teacher has a list of students:

["Tim Jones", "Tom Smith", "Jim Campagno"]

The list includes the first and last name of each student, but our teacher needs to collect a list of just their first names.

So, if our teacher uses #my_collect to collect the first name of his students, it should work like this:

array = ["Tim Jones", "Tom Smith", "Jim Campagno"]
my_collect(array) do |name|
  name.split(" ").first
end

Should return:

["Tim", "Tom", "Jim"]

What if your method was being invoked with a totally different collection and a totally different code block? For example, let's say your #my_collect method is given an argument of a list of programming languages and passed a block that capitalizes the elements yielded to it.

collection = ['ruby', 'javascript', 'python', 'objective-c']
my_collect(collection) do |lang|
  lang.upcase
end

# => ["RUBY", "JAVASCRIPT", "PYTHON", "OBJECTIVE-C"]

Your method should behave the same way––iterating over the given collection and passing each member to the given block––regardless of the content of the collection or the nature of the block.

Make sure to run bundle install before running your tests.

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