From: Robert Klemme <shortcutter@...>
Date: 2008-04-23T15:00:15+09:00
Subject: Re: A couple of questions regarding class design

On 22.04.2008 21:12, Michael W. Ryder wrote:
> Robert Klemme wrote:
>> On 21.04.2008 23:28, Michael W. Ryder wrote:
>>> I chose this after reading about it in Knuth's 2nd volume.  I wanted 
>>> to try to implement the binary greatest common divisor algorithm in 
>>> Ruby. It took a little effort but I was able to implement it without 
>>> any Go Tos.  It is hard to go from languages that require jumping 
>>> around in the code to one that doesn't.  It's a totally different 
>>> mind set.
>>
>> And, does it feel better?  For me it does - for Knuth apparently not.  
>> I haven't felt the need for a goto in ages.  I also rarely use 
>> continue and break in loops.  My impression is that quite a number of 
>> cases where either is chosen can be greatly improved and actually 
>> simplified by choosing a different loop condition.  My 0.02EUR...
> 
> Coming from a background in computers from the 70's when the language 
> was much closer to the metal I never had any problems with Go To or 
> Jump.

Well, you had to use what you got, didn't you?  I believe the reasons 
Basic et al had GOTO was historic as you said: programming languages did 
not have evolved very far from the basis (machine code or assembler if 
you will).

But later people detected deficiencies of this approach and tried to 
come up with better solutions.  I would not want to miss structured 
programming and exceptions.

>  In assembler there is no way to not use Jumps for loops or 
> conditional processing.  Fortran and Basic were much the same way.  I 
> believe Knuth's original works were from this era and of course a lot of 
> his code is in the MIX assembler.
> I can see the reason to eliminate jumping around in code when possible 
> but think they can sometimes make a program easier to read.  I find it 
> easier to read a program that says "If error goto ERROR" over trying to 
> figure out where a Break command goes.

Well, for error handling there is a different mechanism in modern 
languages: exceptions. :-)

Kind regards

	robert