Lisp Code Quotes

Quote may seem a bit of a foreign concept, because few other languages have anything like it. It's closely tied to one of the most distinctive features of Lisp: code and data are made out of the same data structures, and the quote operator is the way we distinguish between them.

On a distant hilltop, twinkling like an early evening star, a white light was flashing. Blouse lowered his telescope. ‘They're repeating "CQ",’ he said. ‘And I believe those longer pauses are when they're aiming their tube in different directions. They're looking for their spies. "Seek You", see? Private Igor?’ ‘Thur?’ ‘You know how that tube works, don't you?’ ‘Oh, yeth, thur. You jutht light a flare in the box, and then it'th just point and click.’ ‘You're not going to answer it, are you, sir?’ said Jackrum, horrified. ‘I am indeed, sergeant,’ said Blouse briskly. ‘Private Carborundum, please assemble the tube. Manickle, please bring the lantern. I shall need to read the code book.’ ‘But that'll give away our position!’ said Jackrum. ‘No, sergeant, because although this term may be unfamiliar to you I intend to what we call "lie",’ said Blouse. ‘Igor, I'm sure you have some scissors, although I'd rather you didn't attempt to repeat the word.’ ‘I have thome of the appliantheth you mention, thur,’ said Igorina stiffly.

Computers speak machine language," Hiro says. "It's written in ones and zeroes -- binary code. At the lowest level, all computers are programmed with strings of ones and zeroes. When you program in machine language, you are controlling the computer at its brainstem, the root of its existence. It's the tongue of Eden. But it's very difficult to work in machine language because you go crazy after a while, working at such a minute level. So a whole Babel of computer languages has been created for programmers: FORTRAN, BASIC, COBOL, LISP, Pascal, C, PROLOG, FORTH. You talk to the computer in one of these languages, and a piece of software called a compiler converts it into machine language. But you never can tell exactly what the compiler is doing. It doesn't always come out the way you want. Like a dusty pane or warped mirror. A really advanced hacker comes to understand the true inner workings of the machine -- he sees through the language he's working in and glimpses the secret functioning of the binary code -- becomes a Ba'al Shem of sorts." "Lagos believed that the legends about the tongue of Eden were exaggerated versions of true events," the Librarian says. "These legends reflected nostalgia for a time when people spoke Sumerian, a tongue that was superior to anything that came afterward." "Is Sumerian really that good?" "Not as far as modern-day linguists can tell," the Librarian says. "As I mentioned, it is largely impossible for us to grasp. Lagos suspected that words worked differently in those days. If one's native tongue influences the physical structure of the developing brain, then it is fair to say that the Sumerians -- who spoke a language radically different from anything in existence today -- had fundamentally different brains from yours. Lagos believed that for this reason, Sumerian was a language ideally suited to the creation and propagation of viruses. That a virus, once released into Sumer, would spread rapidly and virulently, until it had infected everyone." "Maybe Enki knew that also," Hiro says. "Maybe the nam-shub of Enki wasn't such a bad thing. Maybe Babel was the best thing that ever happened to us.

My initial attempt to learn Lisp came to a crashing halt as soon as I saw some sample code. I suppose the same thought ran through my mind that ran through thousands of other minds who were ever in my shoes: "Why on Earth would anyone want to use a language with such horrific syntax?!" I couldn't be bothered to learn a language if its creators couldn't be bothered to give it a pleasant syntax.

The moment I regained my sight I communicated my frustrations to some members of the Lisp sect. Almost immediately I was bombarded by a standard set of responses: Lisp's parentheses are only a superficial matter, Lisp has a huge benefit of code and data being expressed in the same manner (which, obviously, is a huge improvement over XML), Lisp has tremendously powerful metaprogramming facilities that allow programs to write code and modify themselves, Lisp allows for creation of mini-languages specific to the problem at hand, Lisp blurs the distinction between run time and compile time, Lisp, Lisp, Lisp... The list was very impressive. Needless to say none of it made sense.

It’s also very easy to turn Common Lisp REPL code into unit tests, which I tend to do a lot. That is something that’s very hard to do with object-oriented code, which is why idiotic things like dependency injection and Test-Driven Development have to be invented. – Vladimir Sedach

It's a motivating force to implement something; I really recommend it. If you want to understand C, write a C compiler. If you want to understand Lisp, write a Lisp compiler or a Lisp interpreter. I've had people say, “Oh, wow, it's really difficult writing a compiler.” It's not. It's quite easy. There are a lot of little things you have to learn about, none of which is difficult. You have to know about data structures. You need to know about hash tables, you need to know about parsing. You need to know about code generation. You need to know about interpretation techniques. Each one of these is not particularly difficult. I think if you're a beginner you think it's big and complicated so you don't do it. Things you don't do are difficult and things you've done are easy. So you don't even try. And I think that's a mistake.

But deep down, she’s a developer. She’s a developer who loves functional programming because she knows that pure functions and composability are better tools to think with. She eschews imperative programming in favor of declarative modes of thinking. She despises and has a healthy fear of state mutation and non-referential transparency. She favors the lambda calculus over Turing machines because of their mathematical purity. She loves LISPs because she loves her code as data and vice versa.

Matz took the best of list processing from Lisp, and the best of OO from Smalltalk and other languages, and the best of iterators from CLU, and pretty much the best of everything from everyone.