- Practice iterating over array elements.
- Practice manipulating arrays.
- Practice manipulating strings.
- Learn about converting 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 a 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"
- Fork and clone this lab. Run
learn
to see the tests fail. - Write a method
oxford_comma
that takes an argument array of string elements and converts it into a string using the Oxford comma. For example, the array["fiddleheads","okra","kohlrabi"]
should get converted to the string"fiddleheads, okra, and kohlrabi"
.- 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. - Hint: What methods are available to you for converting arrays into strings? You might want to look it up in the Ruby Documentation.
- Hint: Remember, strings can be operated on very similarly to arrays. For instance, you can add elements to the end of strings with the
View Oxford Comma List Formatter on Learn.co and start learning to code for free.