Which equality test does Ruby's Hash use when comparing keys? -

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i have wrapper class around objects want use keys in hash. wrapped , unwrapper objects should map same key.

a simple example this:

class   attr_reader :x   def initialize(inner)     @inner=inner   end   def x; @inner.x; end   def ==(other)     @inner.x==other.x   end end = a.new(o)  #o object allows o.x b = a.new(o) h = {a=>5} p h[a] #5 p h[b] #nil, should 5 p h[o] #nil, should 5

i've tried ==, ===, eq? , hash no avail.

hash uses key.eql? test keys equality. if need use instances of own classes keys in hash, recommended define both eql? , hash methods. hash method must have property a.eql?(b) implies a.hash == b.hash.

so...

class   attr_reader :x   def initialize(inner)     @inner=inner   end   def x; @inner.x; end   def ==(other)     @inner.x==other.x   end    def eql?(other)     self == other   end    def hash     x.hash   end end

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