Ruby Struct utilities: use named parameters to create Struct-based objects and return JSON from Structs

named_struct.rb

# Struct utilities
# Author:: Matt Sullivan (mailto:matt.j.sullivan@gmail.com)

# Attempt to require Ruby Gems; 1.8.X gem support only
begin
  require 'rubygems'
rescue LoadError
  # Ruby Gems not installed
end

require 'json'

# Extends Structs to support named parameter hashes
class NamedStruct < Struct

  # Override the initialize constructor to handle hashes of named parameters
  def initialize *args
    return super unless (args.length == 1 and args.first.kind_of? Hash)
    args.first.each_pair do |k, v|
      # Keys get converted to symbols for consitency
      # Structs in 1.9.x store their members as symbols, but in 1.8.7 and JRuby,
      # they're stored as strings, so ensure you're comparing members as symbols
      self[k.intern] = v if members.map {|x| x.intern}.include? k.intern
    end
  end

end

# Extends NamedStructs to support Hash and JSON outputting
class JSONStruct < NamedStruct

  # Converts a Struct to a hash
  def to_hash
    hash = Hash.new
    self.members.each { |m| hash[m] = self[m] }
    hash
  end

  # Converts a Struct to a JSON string
  def to_json *args
    to_hash.to_json *args
  end

end

I found myself having to redeclare this in almost every project, so I created a gem: https://github.com/rohitpaulk/named_struct