WhinyHash

WhinyHash is a pretty minimalistic gem that offers a slightly tweaked Hash functionality which is primarily intended for the passing of optional parameters. The behavior differs from normal hashes in the following points:

  • reading unset keys results in an error instead of nil
  • setting previously unset keys results in an error
  • merging previously unset keys results in an error

This doesn’t sound like a great improvement, but it simplifies coding quite a lot:


  DEFAULTS = WhinyHash.new({class: "default_class", id: "default_id", value: 0})
  
  def foo(opts={})
    options = DEFAULTS.merge(opts)    # ...do things...

    options[:bar] # raises an error
  end
  
  foo class: 'my_class', value: 23 # fine
  foo clas: 'my_class', value: 23 # raises an error

So you quickly discover

  • usage of undefined options
  • overriding of undefined options

Since we firmly believe in ‘indifferent access’, WhinyHash is derived from ActiveSupport::HashWithIndifferentAccess which is part of activesupport.

License

Copyright © 2010-2011 Peter Horn, Provideal GmbH

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.