Class: NilClass

Inherits:
Object show all
Defined in:
activesupport/lib/active_support/core_ext/object/try.rb,
activesupport/lib/active_support/core_ext/object/json.rb,
activesupport/lib/active_support/core_ext/object/blank.rb,
activesupport/lib/active_support/core_ext/object/to_query.rb,
activesupport/lib/active_support/core_ext/object/duplicable.rb

Instance Method Summary collapse

Instance Method Details

#as_json(options = nil) ⇒ Object

:nodoc:



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# File 'activesupport/lib/active_support/core_ext/object/json.rb', line 74

def as_json(options = nil) #:nodoc:
  self
end

#blank? ⇒ true

nil is blank:

nil.blank? # => true

Returns:

  • (true) 


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# File 'activesupport/lib/active_support/core_ext/object/blank.rb', line 54

def blank?
  true
end

#duplicable? ⇒ Boolean

nil is not duplicable:

nil.duplicable? # => false
nil.dup         # => TypeError: can't dup NilClass

Returns:

  • (Boolean) 


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# File 'activesupport/lib/active_support/core_ext/object/duplicable.rb', line 34

def duplicable?
  false
end

#to_param ⇒ Object

Returns self.



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# File 'activesupport/lib/active_support/core_ext/object/to_query.rb', line 17

def to_param
  self
end

#try(*args) ⇒ Object

Calling try on nil always returns nil. It becomes specially helpful when navigating through associations that may return nil.

nil.try(:name) # => nil

Without try

@person && !@person.children.blank? && @person.children.first.name

With try

@person.try(:children).try(:first).try(:name)



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# File 'activesupport/lib/active_support/core_ext/object/try.rb', line 71

def try(*args)
  nil
end

#try!(*args) ⇒ Object 



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# File 'activesupport/lib/active_support/core_ext/object/try.rb', line 75

def try!(*args)
  nil
end