Ruby SequencedHash | December 29, 2006-->
December 29, 2006Is there a pure-ruby ordered hash? I'm looking for something that will preserve the order in which key/value pairs were entered.
Although one might argue that a Hash that preserves insertion order is not what a Hash is meant to be - sometimes that is exactly what you need.
The new Ruby gem collections contains some classes (right now only two, but more classes are to be expected) that make life a tad easier when working with collections.
The following code excerpt shows an easy usage example for a SequencedHash.
macbook:~ stefan$ sudo gem install collections Successfully installed collections-0.1.1 Installing ri documentation for collections-0.1.1... Installing RDoc documentation for collections-0.1.1...
require 'rubygems' # require 'collections' # # or require 'collections/sequenced_hash' hash = SequencedHash.new hash[:v1] = "v1" hash[:v2] = "v2" hash[:v3] = "v3" puts hash.inspect # => {:v1=>"v1", :v2=>"v2", :v3=>"v3"} puts hash.at(0) # => "v1" puts hash.at(1) # => "v2"
phil76 says: http://me.phillipoertel.com
thanks for the info. i was looking for the same thing recently (coming from php you’re just used to it …). i found two more implementations:
cheers,
phillip