Type of Object

class

1. object.class

[1] pry(main)> "test".class

=> String

[2] pry(main)> [1,2,3].class

=> Array

[3] pry(main)> nil.class

=> NilClass

[4] pry(main)> 1.2.class

=> Float

is_a?

[6] pry(main)> "test".is_a? String

=> true

[7] pry(main)> [1,2,3].is_a? Array

=> true

[8] pry(main)> nil.is_a? NilClass

=> true

[10] pry(main)> 1.2.is_a? Float

=> true

respond_to?

[12] pry(main)> "test".respond_to?(:to_s)

=> true

[13] pry(main)> "test".respond_to?(:to_a)

=> false

[14] pry(main)> [1,2,3].respond_to?(:to_a)

=> true

[17] pry(main)> 1.2.respond_to?(:to_f)

=> true

[18] pry(main)> 1.respond_to?(:to_f)

=> true

instance_of?

[6] pry(main)> "test".instance_of? String

=> true

[7] pry(main)> [1,2,3].instance_of? Array

=> true

[8] pry(main)> nil.instance_of? NilClass

=> true

[10] pry(main)> 1.2.instance_of? Float

=> true

[24] pry(main)> 1.instance_of? Float

=> false

[25] pry(main)> 1.instance_of? Integer

=> true

Ancestors:

pry(main)> 1.class.ancestors

=> [Integer, Numeric, Comparable, Object, PP::ObjectMixin, Kernel, BasicObject]