From: Simon Strandgaard <neoneye@...>
Date: 2003-11-29T04:32:12+09:00
Subject: selfassignment and close

I would like to overload the '+=' operator. But it doesn't seems to be
possible?    If it isn't possible, then how to use the '+' operator and at
the same time get the instance #closed correctly ?


server> ruby a.rb
open 42
open 43
close 42
close 43
-----------------------
open 42
open 43
close 43
server> expand -t2 a.rb 
class Iterator
  def initialize(value)
    @value = value
    puts "open #{@value}"
  end
  def close
    puts "close #{@value}"
  end
  def +(n)
    self.class.new(@value + n)
  end
end

a = Iterator.new(42)
b = a + 1
a.close
b.close

puts "-----------------------"

a = Iterator.new(42)
a += 1   # Question:  How to do selfassignment ?
a.close
# 42 never gets closed!
server>


--
Simon Strandgaard