# Struct

# Creating new structures for data

Struct (opens new window) defines new classes with the specified attributes and accessor methods.

Person = Struct.new :first_name, :last_name

You can then instantiate objects and use them:

person = Person.new 'John', 'Doe'
# => #<struct Person first_name="John", last_name="Doe">

person.first_name
# => "John"

person.last_name
# => "Doe"

# Customizing a structure class

Person = Struct.new :name do
  def greet(someone)
    "Hello #{someone}! I am #{name}!"
  end
end

Person.new('Alice').greet 'Bob'
# => "Hello Bob! I am Alice!"

# Attribute lookup

Attributes can be accessed strings and symbols as keys. Numerical indexes also work.

Person = Struct.new :name
alice = Person.new 'Alice'

alice['name']  # => "Alice"
alice[:name]   # => "Alice"
alice[0]       # => "Alice"

# Syntax

Structure = Struct.new :attribute

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