From: bruno modulix <onurb@...>
Date: 2004-07-13T04:47:23+09:00
Subject: Re: Functional Ruby (Re: Why I don't use Ruby.)

Sean Russell a �crit :
> Mikael Brockman <phubuh@phubuh.org> wrote in message news:<87llhx2hec.fsf@phubuh.org>...
> 
>>Lots of functional languages lack pattern matching.  Scheme, for
>>example.  One can write Scheme-styled code in Ruby.
> 
> 
> In this, and following posts, you make the claim (directly and
> indirectly) that all languages are functional languages, rendering the
> term "functional language"  meaningless, or at least useless.  I
> oppose attempts to generalize words into meaninglessness.
> 
> There *are* good, useful definitions of what constitutes a functional
> languages, and Ruby does not match the criteria for most of them. 
> Probably the most fundamental of all criteria is that the language
> does not allow side-effects, such as assignment.

Scheme, Common Lisp and Caml -- three major fpl's -- allow assignement. 
FWIW, here is the definition of 'functional programming' on the 
c.l.functional's FAQ :

"""
Functional programming is a style of programming that emphasizes the 
evaluation of expressions, rather than execution of commands. The 
expressions in these language are formed by using functions to combine 
basic values. A functional language is a language that supports and 
encourages programming in a functional style.
"""

(http://www.cs.nott.ac.uk/~gmh//faq.html#functional-languages)

Following this definition, Ruby is somewhat on the functional side, 
since it's an 'everything is an expression' language !-)

What else ? Anonymous functions ? Closures ? HOF ? AFAIK, Ruby has it 
all (or I'm I wrong ?)...

(snip)
> 
> Now, a better example would have been to point out OCaml, which is
> *both* functional *and* OO, something which I believe is fundamentally
> impossible, in that it can't be pure OO and pure functional.  However,
> it has a lot of features associated with functional languages, and
> many features associated with OO, so it can claim to be a functional
> language with OO capabilities.

For the record, Common Lisp (and IIRC Scheme) also have a strong support 
for OO.

Bruno