Method: Set#only

Defined in:
lib/autumn/misc.rb

#only ⇒ Object

Returns the only element of a one-element set. Raises an exception if there isn’t exactly one element in the set.

Raises:

  • (IndexError) 


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# File 'lib/autumn/misc.rb', line 83

def only
  raise IndexError, "Set#only called on non-single-element set" unless size == 1
  to_a.first
end