From: Eleanor McHugh <eleanor@...>
Date: 2009-06-02T23:12:54+09:00
Subject: Re: Pythonic indentation (or: beating a dead horse)

On 2 Jun 2009, at 06:20, Andy F wrote:
> +1: new to Ruby and the list, so hope I'm not too rude in saying I'm  
> not impressed with some of the attitudes of 'piss off and use a  
> different language'. Everything's discussable!

I'm not going to defend any 'piss off' attitude that may be inferred  
from some responses to this discussion, but do bear in mind that on  
any mailing list there are discussion topics which have been done to  
death in the past and that when they recur the posters responsible  
will get short shrift.

It's also incredibly rude for someone to make their first post to a  
mailing list with something along the lines of "I'm new to this and  
think it's really cool, but you're all dumb because..." which whilst  
it isn't a fair characterisation of the original post in this thread  
does sum up how some people will have perceived it. Were an  
established poster to raise such a topic, having already demonstrated  
that they understand the trade-offs in the design of Ruby, the  
reaction would be very different - but then again the original post  
itself would probably have been phrased very differently as well.

As to this particular topic. Outside the Python and Haskell  
communities I've seen very little hunger for significant indentation,  
and the benefits are hard to demonstrate as suitably compelling to  
outweigh all of the other changes people would like to see in their  
language of choice. In the case of the Ruby community the main hunger  
seems to be for ever-more-powerful meta-programming techniques and  
extension of the higher order functionals that so much of our code  
comprises of.

In particular Python developers newly acquainted with Ruby tend to  
underestimate the difference between statement-oriented and expression- 
oriented languages. In the former a statement is an isolated entity  
whereas in the latter every expression returns a value, and therefore  
it is thoroughly legitimate to treat that expression as a sub- 
expression. Whilst I don't doubt that expression-based languages can  
be framed in a manner that is compatible with significant indentation,  
in doing so they still need to guarantee maintainability.

Our penchant for a certain variety of meta-programming also makes me  
uneasy about significant indentation and whilst that unease may be  
misplaced I'm sure it's not an isolated phenomenon. The community  
would need to be certain that a change such as significant indentation  
didn't undermine either the fundamental ability to use those  
techniques nor their maintainability, and in hindsight I think a lot  
of the posts opposing such a change - even as an optional feature -  
reflect that.


Ellie

Eleanor McHugh
Games With Brains
http://slides.games-with-brains.net
----
raise ArgumentError unless @reality.responds_to? :reason