From: matz@... (Yukihiro Matsumoto)
Date: 2001-05-16T03:38:11+09:00
Subject: [ruby-talk:15199] Re: operator idea

Hi,

In message "[ruby-talk:15192] Re: operator idea"
    on 01/05/16, Christian Szegedy <szegedy@or.uni-bonn.de> writes:

|I thought that the semantics of a+=x a<<x for thing is the same,
|only their implementations differ. Do I miss something?

Perhaps.  Try:

  a = b = "matz"
  a += " is stupid"
  puts a    # "matz is stupid"
  puts b    # "matz"

  a = b = "matz"
  a << " is a genius"
  puts a    # "matz is a genius"
  puts b    # "matz is a genius"

I believe one should aware of something called "side effect", which is
far important than efficiency.  On a reference counted language, you
can safely avoid side effect (by trying inplace modification when an
object has only one reference), but current Ruby implementation does
not use reference counting.

							matz.