- Iterate over array elements.
- Use various methods to manipulate arrays and strings.
- Convert data types.
In Ruby, there are a few methods available to us for converting data types. For example, it is possible to convert a string to an array, an array into a string, or a range into an array, among other conversions. You can learn more about conversion here, but for now we'll just take a look at a few.
The .split method will convert a string into an array. The .split method
takes an argument of the character in the string on which you want to split it.
For example, if we have a string that contains a comma-separated list of items:
"hippo,giraffe,monkey,horse"We can call .split on it, with an argument of a , ("comma") to get an array
of animal names:
"hippo,giraffe,monkey,horse".split(",")
# => ["hippo", "giraffe", "monkey", "horse"]The .to_a method, when called on a range, can convert a range of numbers to an
array:
(1..10).to_a
# => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]The .join method, when called on an array, will convert it into a string. This
method takes in an optional string argument containing either a character or a
set of characters that will be inserted between each array element, as they are
assembled into a string.
For example, calling .join with no argument will create a string out of the
array's elements by placing each one directly adjacent to the next one:
["a", "b", "c"].join
# => "abc"But calling .join on the same array and giving it an argument of a " :-) "
("smiley face") will place an occurrence of that string, (i.e. the smiley face)
between each letter:
["a", "b", "c"].join(" :-) ")
# => "a :-) b :-) c"Write a method #oxford_comma in the lib/oxford_comma.rb file that takes an
array of string elements as an argument and converts it into a string using the
Oxford comma.
oxford_comma(["fiddleheads", "okra", "kohlrabi"])
# => "fiddleheads, okra, and kohlrabi"Hint: You will need to refer to the section above about converting arrays into strings, but note that coding this method will involve a couple of extra challenges.
Hint: Remember, strings can be operated on very similarly to arrays. For
instance, you can add elements to the end of strings with the << ("shovel")
method just like you can with arrays.
This might be a challenging lab, so take your time using Google and playing around with your code. Good luck and have fun!