MightyStruct

MightyStruct is an object wrapper which gives deep method access to properties. It combines beneficial features from functionally related projects like OpenStruct and Hashie::Mash into an non-inversive, transparant decorator like object wrapper.

Key features

• wraps any object that is an Enumerable (e.g Array or Hash)
• creates method accessors for any object that additionally responds to :keys (e.g. Hash)
• deep method access to object properties
• property accessors are implemented via methods, not method_missing
  • as a result tab completion in pry works
• dispite property accessors, the namespace of wrapped objects isn't touched
• all method calls which don't hit a property accessor are dispatched to the wrapped object
  • results are again wrapped to instances of MightyStruct if possible
• the wrapped object can be retrieved at any time using MightyStruct.to_object(obj)

Example

require "mighty_struct"

hash = {
  a: [
    { b: 1 },
    { b: 2 },
  ],
}

# create it from some hash or array
mighty_struct = MightyStruct.new(hash)

# access deeply nested properties 
mighty_struct.a[0].b # => 1

# call methods transparently on the wrapped objects
mighty_struct.a.last.b # => 2

# get back the original object ... look ma', it's still the same hash
MightyStruct.to_object(mighty_struct).eql?(hash) # => true

Or play with it on your own. It's just one command (line) away.

git clone https://github.com/msievers/mighty_struct.git && cd mighty_struct && bundle && bin/console

Another of this "method invocation" hashes? Really?!

Before I started coding this, I tried the following three alternatives

• OpenStruct
• recursive-open-struct
• Hashie::Mash

But neither of them provided everything I wanted.

	MightyStruct	OpenStruct	recursive-open-struct	Hashie::Mash
deep method access	:heavy_check_mark:	:heavy_multiplication_x:	(:heavy_check_mark:)	:heavy_check_mark:
real method accessors	:heavy_check_mark:	:heavy_check_mark:	:heavy_check_mark:	:heavy_multiplication_x:
works without object dupping	:heavy_check_mark:	:heavy_multiplication_x:	:heavy_multiplication_x:	:heavy_multiplication_x:
transparent method dispatching	:heavy_check_mark:	:heavy_multiplication_x:	:heavy_multiplication_x:	:heavy_multiplication_x:
original object retrieval	:heavy_check_mark:	:heavy_multiplication_x:	:heavy_multiplication_x:	:heavy_multiplication_x:

Why are real methods as property accessors cool?

Method accessors for object properties can either be implemented via method_missing or by defining (singleton) methods. The benefit of real methods is, that if you are using a debugger (e.g. pry), you can use tab completion to discover methods defined on a object. This does not work for method_missing based accessors.

With real method accessors in place, playing with a mighty_struct within pry just feels like working within a shell.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release to create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

1. Fork it ( https://github.com/msievers/mighty_struct/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request