[ILUG] LISP & Prologue

[Smelly Pooh]

In reply to Kenn Humborg's flatulent wordings, 
> On Wed, Feb 02, 2000 at 12:10:37AM +0000, Ross Lynch wrote:
> > Hey all,
> > 
> > Just a few _basic_ questions about LISP & Prologue...
> > 
> > Which is easier first off? Also, how are they in terms of easyness and
> > comparibility with respect to C? And lastly, _is_ Linux the best
> > environment for programming 'em in? (unbiased answers expected ;)).
> 
> According to some LISP is the language of the gods.  It's simple,
> powerful and very easy to write compilers/interpreters for.

This is true, its hard to explain but Lisp is the most syntactically beautiful
and consistent language there is (it even affects my typing style, most of my
sentences contain a section in parenthesis).  The brackets also make code look
exactly like a list (the basic aggregate data type in Lisp) so you can treat
code as data and vice versa, this also leads on to why Lisp makes a great Lisp
interpretter, because when you read in Lisp code, you read it in as a list,
and you use Lisp list operations to parse the code, and interpretting it is
fairly simple because everything is based on a very few ideas, all variables
are pointers, all operations are either procedures or special forms (all basic
algebra operations for example are actually procedures).  Also because the
syntax for Lisp is so consistent the Macro system for Lisp is miles more
advanced than any other language around, Lisp's equivalent of a C 'switch'
statement is a macro using recursive ifs, so are the AND and OR operators.
Local variables and scope are macros of a special form called lambda used to
generate anonymous procedures, it's mad I tell you.

Check out http://www.cs.utexas.edu/users/wilson/schintro/schintro_toc.html
, they teach Scheme and cover bits on how to implement a Scheme
interpretter/compiler using Scheme, a lot of Scheme books seem to like to
teach Scheme this way.
 
> Or something like that...  I read a book on it once years ago
> and a friend of mine had a final year project to write a 
> symbolic calculus package (like Maple/Mathcad/Mathematica) 
> in it.  He said it drove him mad!

Yeah, in DCU Computer Linguistics people have to do it for most of their
degree, it's the most complained about language I know of here (Cobol a
distant second)

> As for programming environments, I imagine that you don't really
> get IDEs for these guys (or if you do, you probably pay big
> wanda).

There are a few, DrScheme (free and available on Unix and Windows) I hear has
an IDE, Harlequin (they also do a development environment for Dylan, a modern
Lisp derivative with Algol/Pascal like syntax, and a very good language it is
too) do an IDE for Common Lisp, I know there are others, you'd be very
surprised at how much Lisp is around.

> They are interpreted, so you'd spend most of your time
> either playing around in the interpreted environment, or
> editing files to feed into the interpreter.

Common misconception with regards to Lisp, there are loads of compilers (full
compilers, lisp to c compilers and bytecode compilers) although I would
consider interpretting as the norm.