module Hashie::Extensions::IgnoreUndeclared

IgnoreUndeclared is a simple mixin that silently ignores undeclared properties on initialization instead of raising an error. This is useful when using a Trash to capture a subset of a larger hash.

Note that attempting to retrieve or set an undeclared property will still raise a NoMethodError, even if a value for that property was provided at initialization.

@example

class Person < Trash
  include Hashie::Extensions::IgnoreUndeclared

  property :first_name
  property :last_name
end

user_data = {
   :first_name => 'Freddy',
   :last_name => 'Nostrils',
   :email => 'freddy@example.com'
}

p = Person.new(user_data) # 'email' is silently ignored

p.first_name # => 'Freddy'
p.last_name  # => 'Nostrils'
p.email      # => NoMethodError