From: Ryan Paul <segphault@...>
Date: 2004-05-13T01:38:54+09:00
Subject: Re: in search of a compelling reason to use ruby....

On Mon, 10 May 2004 10:42:02 +0000, Ryan Paul wrote:

> i'm a python programmer, and I have recently been hearing a lot about
> ruby. A lot of python people seem to think ruby is in some way inferior,
> but I have yet to find any significant differences between the languages.
> The only differences I have found so far have been superficial syntactic
> things. The only real significant difference I have detected, is the
> absence of a module system in ruby.
> 
> I would like to be able to make an objective and educated comparison. Ruby
> seems to have a relatively small, but intensely devoted following.
> Software that inspires such fervent support from a small community usually
> possesses tremendous power that most people are just too dense to discern
> (eg: ocaml, and BeOS). Consequently, I figured it would be worth my time
> to find out what it is that the fanatics find appealing.
> 
> I am looking for:
>     - examples of tangible features that ruby has, which python doesnt.
>     - examples of scenarios where some facet of, or property specific to
>     ruby contributed to the simplification or improvement of a programming
>     project.
>     - facets of the language which may not necessarily be useful, but are
>     notably creative/innovative.
> 
> Additionally, I realize that there is more to a language than its syntax
> and functionality. As a result, I am also interested in hearing about
> facets of the ruby community and ruby ideology, and anything else that
> ruby programmers feel contribute to their affinity for the language. 
> 
> I have a feeling that most of the things that make ruby worth using can
> also be found in python. From the perspective a python programmer who has
> taken only a precursory glance at ruby, it looks like ruby suggests a
> functional style, while python suggests an imperative style. It also looks
> like ruby may be better suited for quick shell scripts, whereas python is
> better suited for bigger programs. I realize that I probably suffer from
> misconceptions, and i'm looking forward to having them corrected.
> 
> I sincerely hope nobody finds any of my comments offensive, I dont mean
> them as criticisms of ruby. I intentionally withhold criticisms until I am
> better versed in the benefits!
> 
> Thanks in advance!
> -- SegPhault

Some general conclusions:

I've learned quite a bit more ruby, and i've ported a bit of python code
by hand for exercise, and I think I can now safely make some useful
generalizations about the differences between the two languages.

Python is simple and consistent, it promotes uniform style between
programs and programmers. Python also works very hard to prevent the
programmer from doing something that might make the language inconsistent,
and it's design often enforces a clear, and concise imperative design.
Syntactic shortcuts and things like native regular expressions are
sacrificed to ensure maximum maintainability and readability.

Ruby is flexible and syntactically mutable. It allows programmers to alter
the behavior of the language itself in contexts where it may be beneficial
to do so. It promotes self extension and alteration, and it introduces a
lot of additional (largely optional) complexity that imbues the language
with the capacity to be, at times, rather arcane. In many cases, ruby
provides convenient syntactic shortcuts to automate things that would have
to be done manually in python.

Ruby idioms dont feel as instantly intuitive as python idioms, but they
seem a great deal more natural. I would definitely say that learning ruby
is a greater challenge than learning python. I would describe several
facets of ruby as 'mind altering'.

Ruby's OO is significantly better than python's. Ruby promotes (and
practically implies) good OO techniques and methodology. This is mostly a
result of Ruby's practice of making all instance variables private, and
the use of a rather elegant means of customizing variable access.

A few examples:

Blocks are a rather simple concept, but they are, initially, extremely
hard to understand, simply because there is nothing else like them. Python
does not provide any profoundly novel or innovative syntactic constructs,
so it easy for any object oriented programmer to grasp.

The axiomatic syntactic classes in python (lists, strings, integers) are
completely and totally immutable. Python does NOT allow you to change or
extend these classes in any way. This is done to ensure utter uniformity,
but it cripples the programmer immensely. Guido Van Rossum, in one of his
essays, says that python could easily support this feature, but he
intentionally chose to disallow it to ensure that programmers wouldn't
accidentally break each others libraries, or the python base libraries for
that matter. Programming around ideology like that is like trying to carve
a sculpture with safety scissors.

In python, we have map, filter, and list comprehensions, all of which can
be used to manipulate lists in very general ways. In order to do certain
things, python users have to stack multiple functions into map statements.
Generally, this is actually pretty simple to do, and makes things somewhat
intuitive. In ruby, there are a multitude of rather oddly named array
functions that have very specific behaviors, most of which can be used
with blocks to concisely describe extremely sophisticated operations.

In conclusion, I feel that python, because of its steadfast consistency,
might be more appropriate for corporate applications, but for power
scripters, who need power and flexibility, nothing beats ruby. I'd like to
know if ruby supports something like C++ namespaces, because something
like that would probably vastly decrease the destructive potential of
inconsistency, without killing its usefulness. I've suggested such a
feature several times in the python world, but nobody seemed to see the
benefit.

--SegPhault