KeySet

KeySet allows you to represent the 4 possible sets of elements:

• All elements (KeySet.all # => KeySet::All)
• No elements (KeySet.non # => KeySet::None)
• Some elements (KeySet.some(['k1', 'k2']) # => KeySet::Some)
• All except some elements (KeySet.all_except_some(['k1', 'k2']) # => KeySet::AllExceptSome)

and do some operations on them, like:

• calculate inverse KeySet (key_set.invert)
• remove a KeySet from another KeySet (key_set.remove(other))
• intersect 2 KeySets (key_set.intersect(other))

The keys in the Some and AllExceptSome key sets are stored in a SortedSet, so they are sorted and without duplicates.

Installation

Add this line to your application's Gemfile:

gem 'key_set'

And then execute:

$ bundle

Or install it yourself as:

$ gem install key_set

Usage

KeySet allows you to represent the 4 possible sets of elements:

• All elements (KeySet.all # => KeySet::All)
• No elements (KeySet.non # => KeySet::None)
• Some elements (KeySet.some(['k1', 'k2']) # => KeySet::Some)
• All except some elements (KeySet.all_except_some(['k1', 'k2']) # => KeySet::AllExceptSome)

and do some operations on them, like:

• calculate inverse KeySet (key_set.invert)
• remove a KeySet from another KeySet (key_set.remove(other))
• intersect 2 KeySets (key_set.intersect(other))

The keys in the Some and AllExceptSome key sets are stored in a SortedSet, so they are sorted and without duplicates.

Creation

KeySet.all # => new KeySet of KeySet::All

KeySet.none # => new KeySet of KeySet::None

KeySet.some(['k1', 'k2']) # => new KeySet of KeySet::Some with keys ['k1', 'k2'] 
KeySet.some([]) # => same as KeySet.none => returns new KeySet::None 

KeySet.all_except_some(['k1', 'k2']) # => new KeySet of KeySet::AllExceptSome with keys ['k1', 'k2'] 
KeySet.all_except_some([]) # => same as KeySet.all => returns new KeySet::All 

Checks

key_set.represents_all? # => true if the key set is a KeySet::All
key_set.represents_none? # => true if the key set is a KeySet::None

.invert

KeySet.all.invert # => KeySet::None
KeySet.none.invert # => KeySet::All
KeySet.some(['k1', 'k2']).invert # => KeySet::AllExceptSome with keys 'k1' and 'k2'
KeySet.all_except_some(['k1', 'k2']).invert # => KeySet::Some with keys 'k1' and 'k2'

.intersect

  #intersect
    All
      KeySet.all.intersect(KeySet.all)
        we have everything, we intersect everything => we have everything
      KeySet.all.intersect(KeySet.none)
        we have everything, we intersect nothing => we have nothing
      KeySet.all.intersect(KeySet.some [key1, key2])
        we have everything, we intersect some => we have some
      KeySet.all.intersect(KeySet.all_except_some [key1, key2])
        we have everything, we intersect all except some => we have all except some
    None
      KeySet.none.intersect(KeySet.all)
        we have nothing, we intersect everything => we have nothing
      KeySet.none.intersect(KeySet.none)
        we have nothing, we intersect nothing => we have nothing
      KeySet.none.intersect(KeySet.some [key1, key2])
        we have nothing, we intersect some => we have nothing
      KeySet.none.intersect(KeySet.all_except_some [key1, key2])
        we have nothing, we intersect all except some => we have nothing
    Some
      KeySet.some([key1, key3]).intersect(KeySet.all)
        we have some, we intersect everything => we have the same some
      KeySet.some([key1, key3]).intersect(KeySet.none)
        we have some, we intersect nothing => we have nothing
      KeySet.some([key1, key3]).intersect(KeySet.some [key1, key2])
        we have some, we intersect some others (that does not include our entire set) => we have the common keys
      KeySet.some([key1, key3]).intersect(KeySet.some [key1, key2, key3])
        we have some, we intersect some others that includes our entire set => we have the common keys, so our former set
      KeySet.some([key1, key3]).intersect(KeySet.all_except_some [key1, key2])
        we have some, we intersect all except others, which includes some of ours => we have the former keys that are not in the other keys
      KeySet.some([key1, key3]).intersect(KeySet.all_except_some [key1, key2, key3])
        we have some, we intersect all except others, which include all our keys => we have nothing
      KeySet.some([key1, key3]).intersect(KeySet.all_except_some [key2, key4])
        we have some, we intersect all except others, none of them are in our keys => we have the same set
    AllExceptSome
      KeySet.all_except_some([key1, key3]).intersect(KeySet.all)
        we have all except some, we intersect everything => we have the same
      KeySet.all_except_some([key1, key3]).intersect(KeySet.none)
        we have all except some, we intersect nothing => we have none
      KeySet.all_except_some([key1, key3]).intersect(KeySet.some [key1, key2])
        we have all except some, we intersect some others => we have the keys in the second that area not in the keys of the first
      KeySet.all_except_some([key1, key3]).intersect(KeySet.some [key1, key3])
        we have all except some, we intersect some of the same keys => we have nothing
      KeySet.all_except_some([key1, key3]).intersect(KeySet.some [key1, key2, key3])
        we have all except some, we intersect some others that includes our entire set => we have the keys in the second that area not in the keys of the first
      KeySet.all_except_some([key1, key3]).intersect(KeySet.all_except_some [key1, key2])
        we have all except some, we intersect all except others (that includes some of the current set) => we get all except the union of keys in the first and in the second
      KeySet.all_except_some([key1, key3]).intersect(KeySet.all_except_some [key1, key2, key3])
        we have all except some, we intersect all except others (that includes the entire of the current set) => we get all except the union of keys in the first and in the second
      KeySet.all_except_some([key1, key3]).intersect(KeySet.all_except_some [key2, key4])
        we have all except some, we intersect all except others (that includes none of the current set) => we get all except the union of keys in the first and in the second
      KeySet.all_except_some([key1, key3]).intersect(KeySet.all_except_some [key1, key3])
        we have all except some, we intersect all except others (that has the same set) => we get the same

.intersect

#remove
  All
    KeySet.all.remove(KeySet.all)
      we have everything, we remove everything => we have nothing
    KeySet.all.remove(KeySet.none)
      we have everything, we remove nothing => we have everything
    KeySet.all.remove(KeySet.some [key1, key2])
      we have everything, we remove some => we have all except those
    KeySet.all.remove(KeySet.all_except_some [key1, key2])
      we have everything, we remove all except some => we have only those
  None
    KeySet.none.remove(KeySet.all)
      we have nothing, we remove everything => we have nothing
    KeySet.none.remove(KeySet.none)
      we have nothing, we remove nothing => we have nothing
    KeySet.none.remove(KeySet.some [key1, key2])
      we have nothing, we remove some => we have nothing
    KeySet.none.remove(KeySet.all_except_some [key1, key2])
      we have nothing, we remove all except some => we have nothing
  Some
    KeySet.some([key1, key3]).remove(KeySet.all)
      we have some, we remove everything => we have nothing
    KeySet.some([key1, key3]).remove(KeySet.none)
      we have some, we remove nothing => we have the same set
    KeySet.some([key1, key3]).remove(KeySet.some [key1, key2])
      we have some, we remove some others (that does not include our entire set) => we have the keys that we have not been removed
    KeySet.some([key1, key3]).remove(KeySet.some [key1, key2, key3])
      we have some, we remove some others that includes our entire set => we have nothing
    KeySet.some([key1, key3]).remove(KeySet.all_except_some [key1, key2])
      we have some, we remove all except others => we have only the keys that we had and they were excluded from the removal
    KeySet.some([key1, key3]).remove(KeySet.all_except_some [key1, key2, key3])
      we have some, we remove all except others, which include all our keys => we have the same keys
    KeySet.some([key1, key3]).remove(KeySet.all_except_some [key2, key4])
      we have some, we remove all except others, none of them are in our keys => we have nothing
  AllExceptSome
    KeySet.all_except_some([key1, key3]).remove(KeySet.all)
      we have all except some, we remove everything => we have nothing
    KeySet.all_except_some([key1, key3]).remove(KeySet.none)
      we have all except some, we remove nothing => we have the same (all but these keys)
    KeySet.all_except_some([key1, key3]).remove(KeySet.some [key1, key2])
      we have all except some, we remove some others => we have all except the ones that we didn't have before and the ones that we don't have now
    KeySet.all_except_some([key1, key3]).remove(KeySet.some [key1, key2, key3])
      we have all except some, we remove some others that includes our entire set => we have all except the new set (that includes the old set)
    KeySet.all_except_some([key1, key3]).remove(KeySet.all_except_some [key1, key2])
      we have all except some, we remove all except others (that includes some of the current set) => we have only the ones that OTHER did not remove, except the ones that THIS was excluding
    KeySet.all_except_some([key1, key3]).remove(KeySet.all_except_some [key1, key2, key3])
      we have all except some, we remove all except others (that includes the entire of the current set) => we have only the ones that OTHER did not remove, except the ones that THIS was excluding
    KeySet.all_except_some([key1, key3]).remove(KeySet.all_except_some [key2, key4])
      we have all except some, we remove all except others (that includes none of the current set) => we get only the ones that the other is not excluding
    KeySet.all_except_some([key1, key3]).remove(KeySet.all_except_some [key1, key3])
      we have all except some, we remove all except others (that has the same set) => we get nothing

Note that removing a AllExceptSome logs a warning, since it is probably not what you want to do.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also 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, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/eturino/ruby_key_set. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the KeySet project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.