Array pad Method with Ruby

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Prompt:

Implement Array#pad and Array#pad!.

Each method accepts a minimum size (non-negative integer) and

an optional pad value as arguments.

If the array’s length is less than the minimum size, Array#pad should return a new array padded with the pad value up to the minimum size.

My challenge is to shorten the code by using .clone and .self. That was the two given hints on the message boards.

The challenge is still trying to grasp non-destructive and destructive way to approach this.

Some folks used the fill method, which takes care of the if/else case and simplify the code beautifully. But I am trying to practice using the ternary operator to see what happen.

My code:

# I had trouble using .length and .size, but .count method also work

class Array
  def pad!(min_size, value = nil)
    padded = min_size - self.count 
    padded.times { self << value }
    self
  end

  def pad(min_size, value = nil)
    self.clone.pad!(min_size, value)
  end
end

Second try, but switching the .clone to .dup

class Array
  def pad!(min_size, value = nil)
        self.length > min_size ? self : (min_size - self.length).times { self << value }
        self
    end

    def pad(min_size, value = nil)
        self.dup.pad!(min_size, value)
    end
end

Updated