method
sole
rails latest stable - Class:
Enumerable
sole()public
Returns the sole item in the enumerable. If there are no items, or more than one item, raises +Enumerable::SoleItemExpectedError+.
["x"].sole # => "x" Set.new.sole # => Enumerable::SoleItemExpectedError: no item found { a: 1, b: 2 }.sole # => Enumerable::SoleItemExpectedError: multiple items found