Set#===

(untyped other) -> bool

===(o)

# File tmp/rubies/ruby-3.4.1/lib/set.rb, line 396
def include?(o)
  @hash[o]
end

Returns true if the given object is a member of the set, and false otherwise.

Used in case statements:

Example

require 'set'

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

Or by itself:

Example

Set[1, 2, 3] === 2   #=> true
Set[1, 2, 3] === 4   #=> false

See also #include? #== #> #<=> also in 4.1 · 4.0 · 3.3 · 3.2 · 3.1 · 3.0