So I needed a way to take a string, and depending on its size, shorten it and fill the remaining space with some arbitrary sequence of characters. Ljust would work, except for the fact that it will fill a string up to a given length, but I only needed to do this when over a certain size. Here is an example:
str = "Somereallylongstring" if str.length > 10 puts str[0..7] + '...' else puts str end # => "Somerea..."
This is the basic idea of what I wanted to do. I decide to make it cleaner and override the String class like so:
class String def lfill(len = self.length, fill = '.') tmp = self[0..(len - 3)] + '...' if self.length - 3 > len return tmp || self end end str = "Somereallylongstring" puts str.lfill(10) #=> "Somerea..."