Re: [Axiom-developer] RE: Boot vs. Lisp

[Bob McElrath]

C Y address@hidden wrote:
> > I agree that using *both* Lisp and BOOT is probably more
> > complicated than it needs to be. But my solution to this
> > would be precisely opposite the solution proposed by Tim.
> > What I would greatly prefer is to replace the Lisp in
> > Axiom with BOOT, where possible. I think the only place
> > where Lisp is required is in the bootstrap for the BOOT
> > compiler itself. And even there, BOOT could be weened from
> > it's mother Lisp and live on it's own like ML, Aldor, and
> > some other languages that started out in Lisp - but I am
> > not really advocating that in the short term.
> 
> In doing so we basically commit to writing our own development
> environments and tools, as well as leaving a language that has an
> established ANSI standard.  That may be worth it, but I'm going to be a
> hard sell. ;-)

Having worked on a couple projects which involved some form of custom
language...

It is far, far more important to have a system which people can jump
into quickly than it is to have a system that is complete, thorough, and
consistent.  If it is easy to get into, it will become complete,
thorough, and consistent eventually.

By writing in a language no one has ever heard of, the project will be
doomed to those that already know it, and those that have a lot of time
on their hands.  Open source development is "itch scratching" and if it
takes a month to figure out how to scratch the itch, most people won't
do it.

Complexity of software scales as exp(size).  Doubling the size
(maintaining a compiler too) means far more than double the work, and
will require far more than double the coders.

I don't really care what language is used.  I've used around 40 in my
life and can learn another.  But Axiom will die if it is necessary to
maintain a compiler also, and it will die if other people can't pick it
up quickly and contribute.  KISS.

I agree wholeheartedly with Tim on much of this:

root address@hidden wrote:
> POINT 3: Boot is a dead language. 
> 
>    There are approximately 10 people still living who have coded in
>    boot and every one of them is doing something else with their
>    life. You have to be careful in boot. It is case sensitive so APPEND
>    is not the same as append. It is often not clear what a construct
>    will translate to and you end up reading the lisp to learn. 
>    A single, misplaced space will change the meaning of the code.
> 
> POINT 4: Boot SERIOUSLY complicates the Axiom system. For instance:
> 
>   1) Bootstrapping boot
> 
>    The boot compiler is written in boot and needs to be compiled
>    using itself. If you have a running Axiom system this is not a
>    problem. However if you start from a clean lisp system it is a
>    big problem. I cheesed up a way to do this but it is fragile and
>    ugly. But given that we build from scratch there is no other way.
> 
>   2) Makefiles come in multiple stages
> 
>    Boot forces Axiom to be built in stages. Thus Axiom cannot use modern
>    tools like ASDF. A pure common lisp Axiom interpreter can be built
>    and loaded directly into a lisp image, interpreted or compiled.
> 
>    Lisp, BOOTSYS, DEPSYS, INTERPSYS, AXIOMSYS. These can all be
>    collapsed if Boot disappears.
> 
>   3) lsp, lisp, clisp, ${LISP}
> 
>    All of these exist because boot exists. For example, .clisp is a
>    translated boot file whereas a lisp file is hand coded. ${LISP}
>    exists to smooth over this bump. I won't go into the historical
>    reasons why these came about but they exist as a side-effect of boot.
> 
>   4) The interpreter has a boot compiler built in
> 
>    There are complications to the interpreter to handle boot-related
>    development from the command line which no-one is ever likely to
>    do again. This code could disappear and, having gone away, simplify
>    the interpreter
> 
> POINT 5: The boot language is undocumented 
> 
>    It is likely to remain so as one of the authors is dead and the other
>    one might be. There are no primary sources of documentation.
> 
> POINT 8: Tools don't support boot
> 
>    Emacs balances lisp parens. It lets me do lisp function lookups. It 
>    understands the lisp syntax including escape chars. SLIME lives in 
>    emacs and provides support. Code walkers walk lisp code. Pretty 
>    printers understand lisp. Debuggers understand lisp (I want to fix
>    it in the language I broke it in). ASDF can manipulate lisp. Programmers 
>    speak lisp. Blank spaces don't break lisp.
> 
>    Boot is unsupported anywhere by anything.
> 
> POINT 9: Where are the programmers?
> 
>    Who will write in boot? I'm the only person likely to be hacking
>    the interpreter for the near future, mostly because it is so big,
>    ugly, unstructured, and undocumented. Even if people code in boot
>    to maintain the interpreter how often will they do that? How will
>    they maintain their skill at writing boot? I've written many, many
>    thousands of lines of lisp and use it continuously. Who are the
>    programmers who will do that in boot?
> 
> POINT 12: Future directions assume lisp
> 
>    Notice that one of the near future goals is to connect Axiom and
>    ACL2. ACL2 understands lisp-ish kind of languages, not boot.
--
Cheers,
Bob McElrath [Univ. of California at Davis, Department of Physics]

    "In science, 'fact' can only mean 'confirmed to such a degree that it would
    be perverse to withhold provisional assent.' I suppose that apples might
    start to rise tomorrow, but the possibility does not merit equal time in
    physics classrooms." -- Stephen Jay Gould (1941 - 2002)

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