From: Stefan Lang <langstefan@...>
Date: 2006-07-12T06:34:16+09:00
Subject: Re: Why Ruby over Python?

On Tuesday 11 July 2006 17:00, jmdeschamps@gmail.com wrote:
> Doug H wrote:
> > howachen@gmail.com wrote:
> > > Besides ROR, can you give me a reason why perfer ruby instead
> > > of python?
> > >
> > > seems to many users, they are very similar in nature...
> > >
> > > such as
> > >
> > > 1. non C or Java style syntax
> > > 2. focus on codes readability, not like Perl
> > > 3. ..
> >
> > Go ask this same question over on comp.lang.python and you'll see
> > why you might prefer ruby.
>
> Funny you ask:
> http://groups.google.ca/group/comp.lang.python/tree/browse_frm/thre
>ad/40d8d11e12cb00ba/12306d4d9b0ce50c?rnum=11&q=ruby+or+python&_done=
>%2Fgroup%2Fcomp.lang.python%2Fbrowse_frm%2Fthread%2F40d8d11e12cb00ba
>%2F7256adbbc7f79afe%3Fq%3Druby+or+python%26rnum%3D1%26#doc_74bfb0743
>eff1367

Interesting. Someone there said that Python is more like Java
and Ruby is more like Smalltalk. I've never written any
Smalltalk, but I know some Lisp. IMO, Ruby and Python are both
somewhere between Lisp and Java, Python closer to Java, Ruby
closer to Lisp.

I have learned many programming languages in the last two years
and the ones I like most are Ruby, Lisp and Haskell. There is one
thing these three languages have in common: It's easy and natural
to construct domain specific languages in them, allowing you
to write code that expresses more directly the problem at hand.

Consider Rake/Rant syntax:

    task :a do
      ...
    end

    task :b => :a do
      ...
    end

Or a well known (in the Haskell community) DSL in Haskell
is Parsec; an example from the Haskell wiki:

    parseInput = do
        dirs <- many dirAndSize
        eof
        return dirs

    data Dir = Dir {dir_size::Integer, dir_name::String} deriving Show

    dirAndSize = do
        size <- many1 digit
        spaces
        dir_name <- anyChar `manyTill` newline
        return (Dir (read size) dir_name)

Of course, Lisp is *the* language for DSL construction.

Python, and more so Java do not allow you to construct a DSL.
Thus in Python and Java, on the syntax level you are always
limited to the few constructs the language provides: Defining
classes and methods, constructing objects, calling methods,
arithmetic expressions, branches via if/else, switch/case.
This gets more limiting the bigger a project grows. Java people
compensate this via huge frameworks that interpret XML files.

Ruby's design is also more coherent than Python's. One example
where Python really f****d up are properties. Python's properties
are an ugly mess, just IMO.

If you already know Java/C#/C++, you'll gain much more in
learning Ruby than Python.

-- 
Stefan