From: Lloyd Zusman <ljz@...>
Date: 2001-07-23T21:03:34+09:00
Subject: [ruby-talk:18335] Re: Ruby, Python and Objects philosophy

Quoting Joe Graham <joe@aiobjects.com>:

> Wasn't there a big /. discussion about this a week or so ago?  If I 
> may interject some thoughts into this matter as well.  Regretfully 
> it belongs on page 75 of that old slashdot discussion but how could 
> I resist?
> *** Warning, below is pure opionated sputter.  Read or discard as 
> needed ***

I have decided to take your "read" option, which has turned out to be
an amply worthwhile decision.

> [ ... lots of interesting stuff snipped to save space ... ]
> 
> [ ... ] Every program I get paid to
> work on involves some custom logging mechanism and whoever I work 
> for has some brilliant idea on this new fancy logging framework 
> that�s going to tell you everything about stupid program X.
> 
> Method defintion( some params )
>   LogMethodEntry( Hard_code_method_name_or_something )
>   Try:
>     Wow_my_code_finally_goes_here
>   Catch:
>     LogThatProblem( Send_That_Error_All_Unformatted_and_ugly_to_our_logger
> )
>    Finally:
>     LogMethodExit( Hard_coded_method_name )
>
> [ ... more good stuff snipped ... ]
>
> [ ... ] So what is the alternative?  If I can override
> the default behavior of all objects in stupid program X than I can have it
> �describe� itself to the logger without writing all that duplicate ugly
> code.  [ ... ]
>
> ..method definition
> #note� someMethod exhibits error trapping behavior
> someMethod( some params )
>  # logging is take care of by Class!
>   Do_my_work_here
> 
> �.outside method call
> catch( methodProblem )
>   tell_FailBlock( what, where )
>   send_methodProblem_back_to_sender
> 
> 
> Now isn�t that pretty?  Notice the missing duplicate code?  Assuming of
> course that we can have objects interested only "aspects" of what is going
> on take care of those things and the code does not have to be duplicated.
> In this case the "aspect" is logging method behavior.  
>
> [ ... ] Also I can get paid big bucks today programming in
> languages like Java that really limit what I can do at runtime.  (ouch!)
> This is not the case with Ruby or Smalltalk.  So what difference does it
> make to the would-be Ruby fleeing from Python / Java / VB or whatever
> programmer?  The answer for me would be �What difference would I want it to
> make?�  Can you make Python act like ruby?  (yes!)  Can you make Ruby act
> like Python? (yes!)  Can you even get those cool block thingies in Python?
> (well you have anonymous functions and if you are really good at tricking
> yourself, yes!)

You have made some good points and illustrated them well.  And I mostly
agree with the opinions you have expounded upon in your sermon.

And now, I have a question:  could you show us how the example above would
be coded in Ruby?  Your pseudo-code is very nice, but a good, concrete,
totally runnable Ruby example of the exact logging scenario that you have
spoken about would be even better.

Thank you very much, in advance.

> [ ... ]

--
 Lloyd Zusman
 ljz@asfast.com