#---
#YAML is a format for representing objects as strings.
#YAML is nice because it’s human-readable
#---

#YAML::dump: convert your Person object array into YAML data

>> require 'yaml'
=> true
>> class Person
>>  attr_accessor :name, :age
>> end
=> nil
>> fred = Person.new
=> #<Person:0x7fed8bc0>
>> fred.name = "Fred Bloggs"
=> "Fred Bloggs"
>> fred.age = 45
=> 45
>> laura = Person.new
=> #<Person:0x7fec7604>
>> laura.name = "Laura Smith"
=> "Laura Smith"
>> laura.age = 23
=> 23
>> test_data = [ fred, laura ]
=> [#<Person:0x7fed8bc0 @name="Fred Bloggs", @age=45>, #<Person:0x7fec7604 @name="Laura Smith", @age=23>]
>> puts YAML::dump(test_data)
---
- !ruby/object:Person
  age: 45
  name: Fred Bloggs
- !ruby/object:Person
  age: 23
  name: Laura Smith
=> nil

#YAML::load: turn YAML code into working Ruby objects.

>> require 'yaml'
=> false
>> class Person
>>  attr_accessor :name, :age
>> end
=> nil
>> yaml_string = <<END_OF_DATA
---
- !ruby/object:Person
  age: 45
  name: Fred Bloggs
- !ruby/object:Person
  age: 23
  name: Laura Smith
END_OF_DATA
=> "---\n- !ruby/object:Person\n  age: 45\n  name: Fred Bloggs\n- !ruby/object:Person\n  age: 23\n  name: Laura Smith\n"
>> test_data = YAML::load(yaml_string)
=> [#<Person:0x7fe71d94 @name="Fred Bloggs", @age=45>, #<Person:0x7fe71ac4 @name="Laura Smith", @age=23>]
>> puts test_data[0].name
Fred Bloggs