Erlang (was Re: Good introduction to functional programming with Python?)

[Fernando Pereira]

In article <92f0il01a5u at news1.newsguy.com>, Alex Martelli
<aleaxit at yahoo.com> wrote:

> "Tim Peters" <tim.one at home.com> wrote in message
> news:mailman.977984412.30211.python-list at python.org...
>     [snip]
> > I haven't used Erlang at all, so that makes it an excellent battlefield:
> no
> > unpleasant haggling over facts <wink>.  I'll hazard a guess based on the
> 
> Right!
> 
> > In the absence of higher-order functions, I can believe programmers don't
> > have much trouble reasoning about types without declarations.  They don't
> 
> The _scarcity_ (not _absence_:-) of HOF in typical Erlang use may be a
> cultural issue (or maybe they just don't buy one all that much in its
> typical use cases); and from that may follow the relative lack of
> interest in its (existing, but 'add-on') type-inferencing possibilities.
The historical reason is that Erlang was originally inspired on logic
and first-order functional programming ideas rather than on
higher-order functional programming. If I remember correctly, the first
Erlang implementation was built on top of Prolog. However, much of
Prolog's machinery (backtracking in particular) was in the way for
concurrent programming (lots of research and ink went into sorting this
out in the logic programming community), so the Erlang team simplified
the language and implementation to still have pattern-matching a la
Prolog but a simple non-backtracking rewriting semantics. The
higher-order additions came later, I believe.

-- F