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+nil [version] [ci]

This gem redefines Ruby's unary + operator to turn null objects into nil. By default, the unary + operator is rarely¹ used by Ruby, so overloading it is not so dangerous as it might have sounded to you when you read it.

Every object that returns true for null? is considered a null object.

¹ (Ruby 2.3 introduced + for String: It will return an unfrozen version of the string)

Setup

Add to your Gemfile:

gem "null_plus"

Usage

class NullObject
  def null?
    true
  end
end

null = NullObject.new

+nil #=> nil
+null #=> nil
+"some object" #=> "some object"

# Useful for settings defaults or checking conditions:
if +null
  fail # will not run
end

value = +null || 42 #=> 42

Hint

Pay attention to proper operator precedence when chaining method class:

class NullObject
  def null?
    true
  end
end

null = NullObject.new

+null.class #=> NullObject
(+null).class #=> NilClass

J-_-L

Copyright (C) 2015 Jan Lelis https://janlelis.com. Released under the MIT license.