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Re: Inheritance

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Doug Hoffman wrote:
> "Costs little" is a subjective term.  This is true only for speed and
> only if all vtable calls are used.  See my response to Bernd.  If speed
> *and* code size are important then that changes things.

See my response, a vtable call is 2+3 bytes on x86, a direct call is 5 
bytes.  Same number of bytes, same number of cycles (in the branch target 
hit case) on x86.

>> In general, no.  Even if you know that your instance variable is an X,
>> you don't know that it isn't a subclass of X.  Early binding serves
>> only to restrict the way code can be resued.
> 
> In general *always* with FMS.  The class of the embedded-object-as
> -instance-variable is not going to change.

That is a severe limitation.  I've both in BerndOOF, embedded-objects that 
can have only one class, and embedded-by-pointer objects that have the 
identical syntax for use, but can have different classes.  Guess what: I 
never use the fixed, inflexible embedded objects.

And yes, I think when I and you talk, we always talk about completely 
different object models.  That's why I mostly gave up on standardization (of 
the model; maybe some meta stuff can still be standardized): Different 
people have so vastly different understandings of what OOP is, and it's 
always like talking to the blind men with the elephant.  Accept it: OOP is 
bigger than you can comprehend.  I know I'm only using a certain part.  My 
OOP is flexible and strong, but I know it is just next to something rigid 
and inflexible.  I've also seen OOP that is thin and not strong, but makes a 
lot of wind when moved, and OOP which is just a massive body (the "bloat").

-- 
Bernd Paysan
"If you want it done right, you have to do it yourself"
http://bernd-paysan.de/

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Inheritance Doug Hoffman <glidedog@gmail.com> - 2013-11-25 06:59 -0500
  Re: Inheritance Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-25 20:01 +0100
    Re: Inheritance Doug Hoffman <glidedog@gmail.com> - 2013-11-26 05:11 -0500
      Re: Inheritance Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-26 22:09 +0100
    Re: Inheritance the_gavino_himself <visphatesjava@gmail.com> - 2013-11-27 15:25 -0800
      Re: Inheritance Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-28 01:39 +0100
        Re: Inheritance Mark Wills <markrobertwills@yahoo.co.uk> - 2013-11-28 01:53 -0800
  Re: Inheritance Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-11-25 15:28 -0600
    Re: Inheritance Doug Hoffman <glidedog@gmail.com> - 2013-11-26 05:11 -0500
      Re: Inheritance Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-26 22:28 +0100
        Re: Inheritance Doug Hoffman <glidedog@gmail.com> - 2013-11-26 17:12 -0500
          Re: Inheritance Bernd Paysan <bernd.paysan@gmx.de> - 2013-11-27 23:07 +0100
      Re: Inheritance Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-11-26 17:11 -0600
        Re: Inheritance Doug Hoffman <glidedog@gmail.com> - 2013-11-27 06:25 -0500
          Re: Inheritance Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-11-27 11:58 -0600

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