From: gga <GGarramuno@...>
Date: 2005-02-17T08:25:31+09:00
Subject: A little bit confused about array+array addition (bug or expected behavior?)

irb> a = [1,2]
=> [1, 2]
irb> a
=> [1, 2, 3, 4]
irb(main):082:0> a
=> [1, 2, 3, 4]

So far so good...


irb(main):082:0> def add(x)
irb(main):084:1>    x += [5,6]
irb(main):085:1> end

irb(main):087:0> add(a)
=> [1, 2, 3, 4, 5, 6]
irb(main):088:0> a
=> [1, 2, 3, 4]        ===>>> uh?  am I not passing stuff by reference?
 where is 5, 6?


irb(main):089:0> def add2(x)
irb(main):089:0>   x << [5,6]
irb(main):089:0> end

irb(main):090:0>  add2(a)
=> [1, 2, 3, 4, [5, 6]]
irb(main):091:0>  a
=> [1, 2, 3, 4, [5, 6]]  ==> seems logical, but then .... why +=
behaves differently?

> ruby -v
ruby 1.8.2 (2004-12-25) [i686-linux]