Airfrost

Here’s a quick and simple Ruby method I wrote that turns an array into a nice, formatted list.

def list(array, options={})
  options[:conjunction] ||= "and"

  list = ""
  array.each_with_index do |string, index|
    list += " " if array.size == 2
    list += options[:conjunction] += " " if array.size == (index + 1)
    list += string.to_s
    list += ", " unless array.size == (index + 1) or array.size == 2
  end

  list = "nothing" if list.empty?
  return list
end

---

Using it should be fairly obvious if you’re familiar with Ruby.

fruits = ["apple", "banana", "peach", "mango"]
list fruits #=> "apple, banana, peach and mango"

numbers = [1, 2]
list fruits, :conjunction => "or" #=> "1 or 2"

empty = []
list empty #=> "nothing"

Since I’m fairly new to Ruby, the way that I’m doing this probably isn’t the most efficient ever, so feel free to sound off in the comments with any improvements.

Update: list() now returns “nothing” instead of (literally) nothing if the array is empty.

Update 2: Apparently, Rails already had a (much better) alternative—Array.to_sentence. Whoops. (Thanks, Noah)