https://github.com/ruby/ostruct
OpenStruct implementation
https://github.com/ruby/ostruct
ruby
Last synced: about 1 month ago
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OpenStruct implementation
- Host: GitHub
- URL: https://github.com/ruby/ostruct
- Owner: ruby
- License: other
- Created: 2017-09-26T09:52:34.000Z (over 7 years ago)
- Default Branch: master
- Last Pushed: 2025-04-30T00:21:43.000Z (about 2 months ago)
- Last Synced: 2025-04-30T01:26:12.908Z (about 2 months ago)
- Topics: ruby
- Language: Ruby
- Homepage:
- Size: 194 KB
- Stars: 124
- Watchers: 34
- Forks: 32
- Open Issues: 15
-
Metadata Files:
- Readme: README.md
- License: COPYING
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README
# OpenStruct [](https://badge.fury.io/rb/ostruct) [](https://stdgems.org/ostruct/) [](https://github.com/ruby/ostruct/actions?query=workflow%3Atest)
An OpenStruct is a data structure, similar to a Hash, that allows the definition of arbitrary attributes with their accompanying values. This is accomplished by using Ruby's metaprogramming to define methods on the class itself.
## Installation
The `ostruct` library comes pre-packaged with Ruby. No installation is necessary.
## Usage
```ruby
require "ostruct"
person = OpenStruct.new
person.name = "John Smith"
person.age = 70
person.name # => "John Smith"
person.age # => 70
person.address # => nil
```
An OpenStruct employs a Hash internally to store the attributes and values and can even be initialized with one:
```ruby
australia = OpenStruct.new(:country => "Australia", :capital => "Canberra")
# => #
```
Hash keys with spaces or characters that could normally not be used for method calls (e.g. ()[]*) will not be immediately available on the OpenStruct object as a method for retrieval or assignment, but can still be reached through the Object#send method.
```ruby
measurements = OpenStruct.new("length (in inches)" => 24)
measurements.send("length (in inches)") # => 24
message = OpenStruct.new(:queued? => true)
message.queued? # => true
message.send("queued?=", false)
message.queued? # => false
```
Removing the presence of an attribute requires the execution of the delete_field method as setting the property value to +nil+ will not remove the attribute.
```ruby
first_pet = OpenStruct.new(:name => "Rowdy", :owner => "John Smith")
second_pet = OpenStruct.new(:name => "Rowdy")
first_pet.owner = nil
first_pet # => #
first_pet == second_pet # => false
first_pet.delete_field(:owner)
first_pet # => #
first_pet == second_pet # => true
```
## Development
After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake test` 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](https://rubygems.org).
## Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/ruby/ostruct.
## License
The gem is available as open source under the terms of the [2-Clause BSD License](https://opensource.org/licenses/BSD-2-Clause).