Issue #6872 has been updated by drbrain (Eric Hodel).


These methods all use "Hash key equality", so #hash and #eql? control the behavior.
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Bug #6872: Array does not specify how it determines uniqueness of values
https://bugs.ruby-lang.org/issues/6872#change-28879

Author: agrimm (Andrew Grimm)
Status: Open
Priority: Normal
Assignee: drbrain (Eric Hodel)
Category: DOC
Target version: 
ruby -v: ruby 1.9.3p194 (2012-04-20 revision 35410) [x86_64-darwin11.4.0]


=begin
The documentation of (({Array#uniq})) , and similar methods, does not specify how values are determined to be unique when a block is not given.

The Stack Overflow answer http://stackoverflow.com/a/8779948/38765 explains that (({Array#uniq})) works on the basis of looking at the hash method of each value in the array. However, this is not explained in the documentation of (({Array#uniq})) , or in (({Object#hash})) .

I think, but I'm not 100% sure, that there are other methods in Array that also use the hash method, such as (({Array#-})) . Ideally, all of these methods should be documented as using the hash method.
=end



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