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How should I write:

if @parent.child.grand_child.attribute.present?
  do_something

without cumbersome nil checkings to avoid exception:

if @parent.child.present? && @parent.child.grandchild.present? && @parent.child.grandchild.attribute.present?

Thank you.

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1 Answer

Rails has object.try(:method):

if @parent.try(:child).try(:grand_child).try(:attribute).present?
   do_something

http://api.rubyonrails.org/classes/Object.html#method-i-try


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