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=== 

        # Set.===

(from ruby core)
---
    ===(o)

---

Returns true if the given object is a member of the set,
and false otherwise.
Used in case statements:
    require 'set'

    case :apple
    when Set[:potato, :carrot]
      "vegetable"
    when Set[:apple, :banana]
      "fruit"
    end
    # => "fruit"

Or by itself:
    Set[1, 2, 3] === 2   #=> true
    Set[1, 2, 3] === 4   #=> false



(This method is an alias for Set#include?.)

Returns true if the set contains the given object.
Note that `include?` and `member?` do not test member
equality using `==` as do other Enumerables.
See also Enumerable#include?

This is MURDOC! A Ruby documentation browser inspired by Smalltalk-80. It allows you to learn about Ruby by browsing through its class hierarchies, and see any of its methods.