Method: Set#add?

Defined in:

lib/set.rb

#add?(o) ⇒ Boolean

Adds the given object to the set and returns self. If the object is already in the set, returns nil.

Set[1, 2].add?(3)                    #=> #<Set: {1, 2, 3}>
Set[1, 2].add?([3, 4])               #=> #<Set: {1, 2, [3, 4]}>
Set[1, 2].add?(2)                    #=> nil

Returns:

• (Boolean)

# File 'lib/set.rb', line 526

def add?(o)
  add(o) unless include?(o)
end