General talk about software patterns

[Pascal Costanza <pascal AT p-cos.net>]

Ralph Johnson wrote:

> Lisp is a wonderful language, and many great things have been done with it.
> However, for some reason, fewer people are using it now than used to use it.

It's rising again. We have organized a Lisp workshop at this year's 
ECOOP. Although the ECOOP organizers rejected it for the same uninformed 
reasons that everyone seems to reject Lisp (including myself a couple of 
years ago), we have organized it independently as a co-located workshop. 
40 people attended the workshop, 34 of which have come to Oslo 
exclusively for that workhop - they didn't even register for the main 
ECOOP conference.

See also http://alu.cliki.net/The%20Road%20to%20Lisp%20Survey for 
indications of rising popularity.

> > But just to put some real case example of "related things in the real world"
> > Paul Graham, btw, made 50 million dollars at Yahoo Stores using these
> > ideas...   He patternized Yahoo stores...
>
> Paul Graham built a system and a company, and sold the company to Yahoo.
> Yahoo took it over and was successful with it, but eventually rewrote it all
> in Java.

No, they have rewritten it in C++, but offer both the Lisp and the C++ 
version for their clients. Reportedly, their clients do not switch to 
the C++ version because they haven't been able to recreate all the 
features that the Lisp version has. (C++ doesn't have closures, and the 
available workarounds doesn't seem to do the job.)

See http://www.ai.mit.edu/~gregs/ll1-discuss-archive-html/msg02367.html 
for a little bit more information.

> This is a typical story.  Why do people take successful systems in
> Lisp (or Smalltalk, or ...) and rewrite them in much more boring and less
> powerful languages?  We need to understand this if we want to make the world
> safe for powerful languages.

Because they make uninformed decisions. There is an anecdote that Lisp 
programmers have applied for jobs at Yahoo, and they were rejected 
because Yahoo says they can't find Lisp programmers. Paradoxial, eh?

Edi Weitz from Hamburg asked for Lisp programmers one or two years ago 
in comp.lang.lisp if people were interested to move to Hamburg for 
continuing a Lisp job in case he is hit by a bus. He has gotten about 15 
responses from all over the world, which convinced his client to indeed 
use Lisp for a project.

We Lispers and Smalltalkers tend to argue from technical grounds and the 
technical advantages of our preferred languages over other languages. 
However, these decisions are typically based purely on grounds of 
popularity (because they presumably get more - think "cheaper" - 
programmers then). Because of that we have to think on two levels at the 
same time, the technical and the social level. We foremostly have to 
provide new arguments on the latter, the former is already set.


Pascal