hash_dot

HashDot

HashDot allows you to get and set your Ruby hash properties with a dot syntax.

  require 'hash_dot'

  user = {name: 'Anna', job: {title: 'Programmer'}}.to_dot

  user.job.title #=> 'Programmer'
  user.job.title = 'Senior Programmer'
  user.job.title #=> 'Senior Programmer'
  user.job.delete(:title)
  user.job.title #=> NoMethodError
  user.job.title = 'Engineer'
  user.job.title #=> 'Engineer'
  user.job.department = 'DevOps'
  user.job.department #=> 'DevOps'
  user.send('beverages=', {}.to_dot)
  user.send('beverages.coffee=', 'Short Black')
  user.send('beverages.coffee') #=> 'Short Black'
  user #=> {:name=>'Anna', :job=>{:title=>'Engineer', :department=>'DevOps'}, :beverages=> { :coffee => 'Short Black'} }

You can also allow dot syntax for all hashes via the class setting.

Hash.use_dot_syntax = true

{name: 'Pat'}.name #=> 'Pat'

By default HashDot raises a NoMethodError when accessing a non-existent key with the dot syntax. The value of Hash#default can be used instead, either globally or per-instance, via:

# globally
Hash.use_dot_syntax = true
Hash.hash_dot_use_default = true
{}.a #=> 'default'

# per instance
h = Hash.new('default').to_dot(use_default: true)
h.a #=> 'default'
{}.to_dot.a #=> NoMethodError

Installation

Add this line to your application's Gemfile:

gem 'hash_dot'

And then execute:

$ bundle

Or install it yourself as:

$ gem install hash_dot

Benchmarks

Benchmarks should be taken with a grain of salt, as always. For example, OpenStruct is much slower to initialize, but calls its methods faster once initialized. The OpenStruct solution also can't traverse more than a single dot without recursively instantiating all sub-hashes into OpenStructs.

require 'ostruct'
require 'benchmark'
require 'hash_dot'

user = { address: { category: { desc: 'Urban'}}}.to_dot

iterations = 50000

Benchmark.bm(8) do |bm|
  bm.report("Default Notation   :") {
    iterations.times do; user[:address][:category][:desc]; end
  }

  bm.report("Dot Notation       :") {
    iterations.times do; user.address.category.desc; end
  }

  bm.report("OpenStruct         :") {
    iterations.times do; OpenStruct.new(user); end
  }

  # Minus OpenStruct instantiation cost
  os_user = OpenStruct.new(user)
  bm.report("OpenStruct Single  :") {
    iterations.times do; os_user.address; end
  }

  bm.report("Dot Notation Single:") {
    iterations.times do; user.address; end
  }
end

# Benchmark Example
#                       user     system      total        real
Default Notation   :  0.010000   0.000000   0.010000 (  0.008807)
Dot Notation       :  0.190000   0.000000   0.190000 (  0.195819)
OpenStruct         :  0.400000   0.010000   0.410000 (  0.399542)
OpenStruct Single  :  0.010000   0.000000   0.010000 (  0.011259)
Dot Notation Single:  0.080000   0.000000   0.080000 (  0.082606)

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/adsteel/hash_dot. 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.