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Re: Not understanding OOP stuff

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Ben Bacarisse wrote:

> […] That's all part of the late binding that some people consider so 
> important.
> 
> […] in a message passing language the message can fail if the
> object does not implement that particular message.  In your examples,
> the message sending (which is just a function call) can't fail for that
> reason.
> 
> To my mind, message passing would look rather more like:
> 
>   var msg = ["foo", 42, 23];
>   o.process_message(msg);
> 
> This would succeed or fail depending on whether o's prototype chain
> included a foo method at that time.

Calling a method on an object referred to by “o” – which in OOP/UML terms is 
equivalent to sending a message to an object where the call’s arguments are 
the message contents – *does* fail if that object does not have, and no 
object in its prototype chain has, a method of that name *at runtime*.  
*That* *is* late binding.

  try
  {
    o.foo(42, 23);
  }
  catch (e)
  {
    /* TypeError: o.foo is not a function */
  }

ISTM you are confusing messages sent to objects with those appended to a 
message queue (which does not need to pertain to objects).  Maybe because 
you are accustomed to programming languages or software systems where 
object-orientation is implemented in that way.

-- 
PointedEars
FAQ: <http://PointedEars.de/faq> | <http://PointedEars.de/es-matrix>
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Not understanding OOP stuff bit-naughty@hotmail.com - 2017-07-21 09:11 -0700
  Re: Not understanding OOP stuff JJ <jj4public@vfemail.net> - 2017-07-22 19:36 +0700
  Re: Not understanding OOP stuff Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-07-23 18:12 +0200
    Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-23 09:19 -0700
      Re: Not understanding OOP stuff Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-07-23 20:10 +0100
        Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-23 12:42 -0700
          Re: Not understanding OOP stuff Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-07-23 22:03 +0100
            Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-23 14:18 -0700
              Re: Not understanding OOP stuff Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-07-24 03:22 +0100
                Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-23 21:44 -0700
            Re: Not understanding OOP stuff Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-07-24 03:49 +0100
              Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-23 21:50 -0700
                Re: Not understanding OOP stuff John G Harris <niam@jghnorth.org.uk.invalid> - 2017-07-24 19:50 +0100
                Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-24 12:00 -0700
                Re: Not understanding OOP stuff John G Harris <niam@jghnorth.org.uk.invalid> - 2017-07-25 09:29 +0100
                Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-25 05:58 -0700
              Re: Not understanding OOP stuff Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-07-24 11:04 +0200
                Re: Not understanding OOP stuff Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-07-25 00:09 +0100
                Re: Not understanding OOP stuff John G Harris <niam@jghnorth.org.uk.invalid> - 2017-07-25 09:20 +0100
                Re: Not understanding OOP stuff Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-07-25 11:31 +0100
                Re: Not understanding OOP stuff Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-07-25 17:02 +0200
                Re: Not understanding OOP stuff Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-07-25 23:47 +0100
                Re: Not understanding OOP stuff Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-07-27 15:15 +0200
            Re: Not understanding OOP stuff Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-07-24 10:33 +0200
              Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-24 02:13 -0700
          Re: Not understanding OOP stuff John G Harris <niam@jghnorth.org.uk.invalid> - 2017-07-24 11:15 +0100
            Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-24 03:58 -0700
              Re: Not understanding OOP stuff John G Harris <niam@jghnorth.org.uk.invalid> - 2017-07-25 09:42 +0100
                Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-25 05:59 -0700
                Re: Not understanding OOP stuff John G Harris <niam@jghnorth.org.uk.invalid> - 2017-07-25 18:32 +0100
        Re: Not understanding OOP stuff Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-07-23 22:42 +0200
          Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-23 13:55 -0700
          Re: Not understanding OOP stuff John G Harris <niam@jghnorth.org.uk.invalid> - 2017-07-24 11:18 +0100
            Re: Not understanding OOP stuff Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-07-24 15:19 +0200
      Re: Not understanding OOP stuff "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-07-24 10:20 -0700
        Re: Not understanding OOP stuff Julio Di Egidio <julio@diegidio.name> - 2017-07-24 11:46 -0700
          Re: Not understanding OOP stuff "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-07-25 05:37 -0700
    Re: Not understanding OOP stuff John G Harris <niam@jghnorth.org.uk.invalid> - 2017-07-24 11:04 +0100
      Re: Not understanding OOP stuff Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-07-24 16:04 +0200

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