From: Belorion <belorion@...>
Date: 2008-04-05T04:11:31+09:00
Subject: The ||= assignment operator

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It was my understanding that the ||= assignment operator assigned the value
on the right-hand side if and only if the left hand side did not already
have a value:

irb(main):001:0> x = true
=> true
irb(main):002:0> x ||= "ruby"
=> true
irb(main):003:0> x
=> true
And, likewise, with nil:

irb(main):014:0> x = nil
=> nil
irb(main):015:0> x ||= "ruby"
=> "ruby"
irb(main):016:0> x
=> "ruby"
However, I do not understand this behavior:

irb(main):019:0> x = false
=> false
irb(main):020:0> x ||= "ruby"
=> "ruby"
irb(main):021:0> x
=> "ruby"


We know that false != nil, and yet the ||= will assign if the left hand side
is false?

regards,
Matt

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