Ruby: Calling class method from instance

Question

In Ruby, how do you call a class method from one of that class\'s instances? Say I have

class Truck
  def self.default_make
    # Class method.
    \"mac\"
  end         


        

Answer 1

To access a class method inside a instance method, do the following:

self.class.default_make

Here is an alternative solution for your problem:

class Truck

  attr_accessor :make, :year

  def self.default_make
    "Toyota"
  end

  def make
    @make || self.class.default_make
  end

  def initialize(make=nil, year=nil)
    self.year, self.make = year, make
  end
end

Now let's use our class:

t = Truck.new("Honda", 2000)
t.make
# => "Honda"
t.year
# => "2000"

t = Truck.new
t.make
# => "Toyota"
t.year
# => nil