Immutable struct with getters

We can defined methods in the struct to become the getters of the attributes, but this too is boring.

examples/struct/immutable_struct_with_getter.cr

struct Person
  def initialize(@name : String, @email : String)
  end

  def name
    @name
  end

  def email
    @email
  end
end

foo = Person.new("Foo", "me@foo.bar")
p! foo
p! foo.name
p! foo.email

foo # => Person(@name="Foo", @email="me@foo.bar")
foo.name # => "Foo"
foo.email # => "me@foo.bar"