Dry::Types integration with fear allows using Fear::Option as optional type for Dry::Types
Install the gem and add to the application's Gemfile by executing:
$ bundle add dry-types-fear
If bundler is not being used to manage dependencies, install the gem by executing:
$ gem install dry-types-fear
Load the :fear_option extension in your application.
require 'dry-types'
require 'dry/types/fear'
Dry::Types.load_extensions(:fear_option)
module Types
include Dry.Types()
endAppend .option to a Type to return a Fear::Option object:
Types::Option::Strict::Integer[nil]
#=> Fear.none
Types::Option::Coercible::String[nil]
#=> Fear.none
Types::Option::Strict::Integer[123]
#=> Fear.some(123)
Types::Option::Strict::String[123]
#=> Fear.some(123)
Types::Option::Coercible::Float['12.3']
#=> Fear.some(12.3)'Option' types can also accessed by calling .option on a regular type:
Types::Strict::Integer.option # equivalent to Types::Option::Strict::IntegerYou can define your own optional types:
option_string = Types::Strict::String.option
option_string[nil]
# => Fear.none
option_string[nil].map(&:upcase)
# => Fear.none
option_string['something']
# => Fear.some('something')
option_string['something'].map(&:upcase)
# => Fear.some('SOMETHING')
option_string['something'].map(&:upcase).get_or_else { 'NOTHING' }
# => "SOMETHING"You can use it with dry-struct as well:
class User < Dry::Struct
attribute :name, Types::Coercible::String
attribute :age, Types::Coercible::Integer.option
end
user = User.new(name: 'Bob', age: nil)
user.name #=> "Bob"
user.age #=> Fear.none
user = User.new(name: 'Bob', age: 42)
user.age #=> Fear.some(42) 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 the gemspec, and then run bundle exec rake release, which will create a git
tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.
Bug reports and pull requests are welcome on GitHub at https://github.com/bolshakov/dry-types-fear.
