Ruby: How to make an object that works with multiple assignment
Ruby allows multiple assignment:
a, b, c = o
In order to prove multiple values from a single object, Ruby calls #to_a on the object:
o = String.new('O')
def o.to_a
[1,2,3]
end
a, b, c = o # Implicit call to #to_a here
a # => 1
b # => 2
c # => 3
Hence, if you want your class to support multiple assignment, make sure to define a #to_a method.
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