shaswat123/etnlp · Datasets at Hugging Face

text stringlengths 0 412k
programs that manipulate them. In Lisp, these programs are called
macros. They are programs that write programs.Programs that write programs? When would you ever want to do that?
Not very often, if you think in Cobol. All the time, if you think
in Lisp. It would be convenient here if I could give an example
of a powerful macro, and say there! how about that? But if I did,
it would just look like gibberish to someone who didn't know Lisp;
there isn't room here to explain everything you'd need to know to
understand what it meant. In
Ansi Common Lisp I tried to move
things along as fast as I could, and even so I didn't get to macros
until page 160.But I think I can give a kind of argument that might be convincing.
The source code of the Viaweb editor was probably about 20-25%
macros. Macros are harder to write than ordinary Lisp functions,
and it's considered to be bad style to use them when they're not
necessary. So every macro in that code is there because it has to
be. What that means is that at least 20-25% of the code in this
program is doing things that you can't easily do in any other
language. However skeptical the Blub programmer might be about my
claims for the mysterious powers of Lisp, this ought to make him
curious. We weren't writing this code for our own amusement. We
were a tiny startup, programming as hard as we could in order to
put technical barriers between us and our competitors.A suspicious person might begin to wonder if there was some
correlation here. A big chunk of our code was doing things that
are very hard to do in other languages. The resulting software
did things our competitors' software couldn't do. Maybe there was
some kind of connection. I encourage you to follow that thread.
There may be more to that old man hobbling along on his crutches
than meets the eye.Aikido for StartupsBut I don't expect to convince anyone
(over 25)
to go out and learn
Lisp. The purpose of this article is not to change anyone's mind,
but to reassure people already interested in using Lisp-- people
who know that Lisp is a powerful language, but worry because it
isn't widely used. In a competitive situation, that's an advantage.
Lisp's power is multiplied by the fact that your competitors don't
get it.If you think of using Lisp in a startup, you shouldn't worry that
it isn't widely understood. You should hope that it stays that
way. And it's likely to. It's the nature of programming languages
to make most people satisfied with whatever they currently use.
Computer hardware changes so much faster than personal habits that
programming practice is usually ten to twenty years behind the
processor. At places like MIT they were writing programs in
high-level languages in the early 1960s, but many companies continued
to write code in machine language well into the 1980s. I bet a
lot of people continued to write machine language until the processor,
like a bartender eager to close up and go home, finally kicked them
out by switching to a risc instruction set.Ordinarily technology changes fast. But programming languages are
different: programming languages are not just technology, but what
programmers think in. They're half technology and half religion.[6]
And so the median language, meaning whatever language the median
programmer uses, moves as slow as an iceberg. Garbage collection,
introduced by Lisp in about 1960, is now widely considered to be
a good thing. Runtime typing, ditto, is growing in popularity.
Lexical closures, introduced by Lisp in the early 1970s, are now,
just barely, on the radar screen. Macros, introduced by Lisp in the
mid 1960s, are still terra incognita.Obviously, the median language has enormous momentum. I'm not
proposing that you can fight this powerful force. What I'm proposing
is exactly the opposite: that, like a practitioner of Aikido, you
can use it against your opponents.If you work for a big company, this may not be easy. You will have
a hard time convincing the pointy-haired boss to let you build
things in Lisp, when he has just read in the paper that some other
language is poised, like Ada was twenty years ago, to take over
the world. But if you work for a startup that doesn't have
pointy-haired bosses yet, you can, like we did, turn the Blub
paradox to your advantage: you can use technology that your
competitors, glued immovably to the median language, will never be
able to match.If you ever do find yourself working for a startup, here's a handy
tip for evaluating competitors. Read their job listings. Everything
else on their site may be stock photos or the prose equivalent,
but the job listings have to be specific about what they want, or
they'll get the wrong candidates.During the years we worked on Viaweb I read a lot of job descriptions.
A new competitor seemed to emerge out of the woodwork every month
or so. The first thing I would do, after checking to see if they
had a live online demo, was look at their job listings. After a
couple years of this I could tell which companies to worry about
and which not to. The more of an IT flavor the job descriptions
had, the less dangerous the company was. The safest kind were the
ones that wanted Oracle experience. You never had to worry about
those. You were also safe if they said they wanted C++ or Java
developers. If they wanted Perl or Python programmers, that would
be a bit frightening-- that's starting to sound like a company
where the technical side, at least, is run by real hackers. If I
had ever seen a job posting looking for Lisp hackers, I would have
been really worried.
Notes[1] Viaweb at first had two parts: the editor, written in Lisp,
which people used to build their sites, and the ordering system,
written in C, which handled orders. The first version was mostly
Lisp, because the ordering system was small. Later we added two
more modules, an image generator written in C, and a back-office
manager written mostly in Perl.In January 2003, Yahoo released a new version of the editor
written in C++ and Perl. It's hard to say whether the program is no
longer written in Lisp, though, because to translate this program
into C++ they literally had to write a Lisp interpreter: the source
files of all the page-generating templates are still, as far as I
know, Lisp code. (See Greenspun's Tenth Rule.)[2] Robert Morris says that I didn't need to be secretive, because
even if our competitors had known we were using Lisp, they wouldn't
have understood why: "If they were that smart they'd already be
programming in Lisp."[3] All languages are equally powerful in the sense of being Turing
equivalent, but that's not the sense of the word programmers care
about. (No one wants to program a Turing machine.) The kind of

programs that manipulate them. In Lisp, these programs are called

macros. They are programs that write programs.Programs that write programs? When would you ever want to do that?

Not very often, if you think in Cobol. All the time, if you think

in Lisp. It would be convenient here if I could give an example

of a powerful macro, and say there! how about that? But if I did,

it would just look like gibberish to someone who didn't know Lisp;

there isn't room here to explain everything you'd need to know to

understand what it meant. In

Ansi Common Lisp I tried to move

things along as fast as I could, and even so I didn't get to macros

until page 160.But I think I can give a kind of argument that might be convincing.

The source code of the Viaweb editor was probably about 20-25%

macros. Macros are harder to write than ordinary Lisp functions,

and it's considered to be bad style to use them when they're not

necessary. So every macro in that code is there because it has to

be. What that means is that at least 20-25% of the code in this

program is doing things that you can't easily do in any other

language. However skeptical the Blub programmer might be about my

claims for the mysterious powers of Lisp, this ought to make him

curious. We weren't writing this code for our own amusement. We

were a tiny startup, programming as hard as we could in order to

put technical barriers between us and our competitors.A suspicious person might begin to wonder if there was some

correlation here. A big chunk of our code was doing things that

are very hard to do in other languages. The resulting software

did things our competitors' software couldn't do. Maybe there was

some kind of connection. I encourage you to follow that thread.

There may be more to that old man hobbling along on his crutches

than meets the eye.Aikido for StartupsBut I don't expect to convince anyone

(over 25)

to go out and learn

Lisp. The purpose of this article is not to change anyone's mind,

but to reassure people already interested in using Lisp-- people

who know that Lisp is a powerful language, but worry because it

isn't widely used. In a competitive situation, that's an advantage.

Lisp's power is multiplied by the fact that your competitors don't

get it.If you think of using Lisp in a startup, you shouldn't worry that

it isn't widely understood. You should hope that it stays that

way. And it's likely to. It's the nature of programming languages

to make most people satisfied with whatever they currently use.

Computer hardware changes so much faster than personal habits that

programming practice is usually ten to twenty years behind the

processor. At places like MIT they were writing programs in

high-level languages in the early 1960s, but many companies continued

to write code in machine language well into the 1980s. I bet a

lot of people continued to write machine language until the processor,

like a bartender eager to close up and go home, finally kicked them

out by switching to a risc instruction set.Ordinarily technology changes fast. But programming languages are

different: programming languages are not just technology, but what

programmers think in. They're half technology and half religion.[6]

And so the median language, meaning whatever language the median

programmer uses, moves as slow as an iceberg. Garbage collection,

introduced by Lisp in about 1960, is now widely considered to be

a good thing. Runtime typing, ditto, is growing in popularity.

Lexical closures, introduced by Lisp in the early 1970s, are now,

just barely, on the radar screen. Macros, introduced by Lisp in the

mid 1960s, are still terra incognita.Obviously, the median language has enormous momentum. I'm not

proposing that you can fight this powerful force. What I'm proposing

is exactly the opposite: that, like a practitioner of Aikido, you

can use it against your opponents.If you work for a big company, this may not be easy. You will have

a hard time convincing the pointy-haired boss to let you build

things in Lisp, when he has just read in the paper that some other

language is poised, like Ada was twenty years ago, to take over

the world. But if you work for a startup that doesn't have

pointy-haired bosses yet, you can, like we did, turn the Blub

paradox to your advantage: you can use technology that your

competitors, glued immovably to the median language, will never be

able to match.If you ever do find yourself working for a startup, here's a handy

tip for evaluating competitors. Read their job listings. Everything

else on their site may be stock photos or the prose equivalent,

but the job listings have to be specific about what they want, or

they'll get the wrong candidates.During the years we worked on Viaweb I read a lot of job descriptions.

A new competitor seemed to emerge out of the woodwork every month

or so. The first thing I would do, after checking to see if they

had a live online demo, was look at their job listings. After a

couple years of this I could tell which companies to worry about

and which not to. The more of an IT flavor the job descriptions

had, the less dangerous the company was. The safest kind were the

ones that wanted Oracle experience. You never had to worry about

those. You were also safe if they said they wanted C++ or Java

developers. If they wanted Perl or Python programmers, that would

be a bit frightening-- that's starting to sound like a company

where the technical side, at least, is run by real hackers. If I

had ever seen a job posting looking for Lisp hackers, I would have

been really worried.

Notes[1] Viaweb at first had two parts: the editor, written in Lisp,

which people used to build their sites, and the ordering system,

written in C, which handled orders. The first version was mostly

Lisp, because the ordering system was small. Later we added two

more modules, an image generator written in C, and a back-office

manager written mostly in Perl.In January 2003, Yahoo released a new version of the editor

written in C++ and Perl. It's hard to say whether the program is no

longer written in Lisp, though, because to translate this program

into C++ they literally had to write a Lisp interpreter: the source

files of all the page-generating templates are still, as far as I

know, Lisp code. (See Greenspun's Tenth Rule.)[2] Robert Morris says that I didn't need to be secretive, because

even if our competitors had known we were using Lisp, they wouldn't

have understood why: "If they were that smart they'd already be

programming in Lisp."[3] All languages are equally powerful in the sense of being Turing

equivalent, but that's not the sense of the word programmers care

about. (No one wants to program a Turing machine.) The kind of