The Roots of Lisp (2001)
paulgraham.com
paulgraham.com
One could argue that Church's (1930s) lambda calculus, which underlies LISP, is a closer analogue to Euclid's distillation of the essence of Geometry.
With the minimal addition of pure binary IO, the lambda calculus is easily transformed into an untyped programming language [1]. On the other hand, full blown and richly typed pure functional programming languages like Haskell remain semantically faithful to their lambda calculus underpinnings.
http://www.flownet.com/ron/lambda-calculus.html
[EDIT] Heh, I just realized that we corresponded on this back when I wrote it in 2014! Small world.
certainly lambda calculus was used to define functions in lisp, as seen in the original lisp paper (or the most famous one).
http://jmc.stanford.edu/articles/recursive.html
lambda calculus was a tool, but it seems godel and turing's work on computing machines and recursive functions were more fundamental to the original lisp.
Lambda calculus, as articulated in Church's 1935 paper, gives us a way to understand computability. But if we look specifically at Operation II in the paper (p. 347), what we have is the lambda function in Scheme. Given that every function in Scheme (including special forms) is equivalent to some lambda function, it seems that in virtue of Operation II we can say that lambda calculus underlies Scheme.
Whether we can push this further to say that lambda calculus underlies McCarthy's initial conception of LISP, or some arbitrary version of Common Lisp, I do not know for certain. But if all these versions treat lambda functions the same way as Scheme does (in relevant respects), then the claim holds for Lisp generally.
[1]: Church. An Unsolvable Problem of Elementary Number Theory. _American Journal of Mathematics_, Vol. 58, No. 2. (Apr., 1936), pp. 345-363.
is this theorized somewhere ? Or am i just dreaming ?
(dynamic) functional programming enables very 'easy' succinct abstractions through combing out concretions and composing functions out of a general tool-set. Think code-reuse in the small.
With some discipline you naturally end up with a very data-oriented codebase, where the specificity of your application/library ends up in your data-structures.
Now these data-structures are really just plain data, without specific behavior attached to them, so they embody the (maybe almost) declarative part of your program/system. The next step would be to polish them to make them more human readable.
An additional feature of Lisps is their homoiconicity and macros. These come into play when plain data-structures are not the right fit anymore. Typically you want to handle some user/client defined behavior. You can now transform the syntax of the language itself to clean up your API to reduce boilerplate and increase readability.
In a sense you have now programmed your own DSL.
https://stacks.stanford.edu/file/druid:qh147kq8662/SC1041_SA...
(func var0 var1 ... varn)
Could it be that the design of LISP is inspired by the structure of the genetic code?
But this presented other problems, namely that you might end up coding your libraries on an island, and no one else could understand your code. This is probably why Lisp is mostly more powerful when there is only one or a few programmers working on the code base.
But with the increase in other programming languages, and the massive amounts of other libraries out there, then is this macro system really all that necessary anymore?
Having more libraries than most languages doesn't nullify the use of macros, macros are usually discouraged in application code because they don't compose well, don't make a macro if a function will do
However having macros meant that when go popularised CSP concurrency at the language level it meant we didn't need to change the language (for all variants of Clojure) it just meant we could make a library with macros to do CSP concurrency and it works on the browser on the server etc
Completely opt in, well documented as a library and we didn't weigh down the language with this feature, if or when the next big concurrency thing comes along we won't be looking to deprecate go channels from the language
Macros are incredibly powerful and you probably won't need them often but for those small cases of scratching a particular itch they're a get out of jail free card
To me it is not very common for (very) technical people to be good at both tech and business!
It's hard to describe how easy it was to make money in the late 90's with even little technical skill and tiniest amount of business understanding. We were making money hand over fist knowing next to nothing.
PG sold his company for $50 million, we sold ours for $5 million after we took the mountain of cash out of it (another $5 million). After reading how PG did it, I think his genius was paying $16,000 a month for a PR firm. He understood the value of PR, we didn't. http://www.paulgraham.com/submarine.html
His essays, HackerNews and Y combinator are expression of this understanding. He has created expanding self-reinforcing network of affordable PR and connections for startups. That's the real scarcity in the startup scene. Being accepted into a batch is valuable. Instead of hiring PR firm, PR firm accepts you and stamps you with the Y Combinator brand.
See related: http://www.paulgraham.com/submarine.html
Bill Joy co-founded SUN - but also wrote ex, vi, the BSD UNIX tcp/ip stack, and other things.
Marc Andreessen wrote Mosaic and Netscape - and is a famous VC person now (of Andreessen Horowitz fame).
Bill Gates, also very technical (wrote early MS programs, BASIC interpreters etc).
Eric Schmidt (ex Google CEO) wrote Lex (the lexer, now more known by its GNU port, flex) and was SUN's first programmer.
That doesn't happen in poker.
Lisp is ideal for changing on a dime, at least for a small team.
Or is it better to just go straight to Clojure these days?
SICP is great but not really about Lisp.
I recommend Norvig's PAIP [1] or Graham's ANSI Common Lisp [2].
Another book that's often recommended is Practical Common Lisp but I think it's dated and hasn't aged well. It's also nowhere near as mind expanding as PAIP/Graham's books.
[1] https://github.com/norvig/paip-lisp
[2] PDFs can be found on Google
Clojure is not recommended as it is very different to Lisp.
Lisp code needs to be entirely rewritten before it will run on Clojure. That is not true for Common Lisp, Emacs Lisp and even Scheme.
- If you want something practical - do try Clojure. Don't listen to JVM haters and Lisp "purists". JVM is a pretty robust piece of tech and Clojure is a proper Lisp dialect. Besides, Clojurescript is a lot of fun.
- If you like Lua, and want to make simple, fun games try Fennel. If you're into math and enjoy playing with fractals and such, do try Racket.
- If you are serious about Lisp, sooner or later you may want to learn Common Lisp. Especially if you already using Emacs and want to improve your emacs-lisp skills.
* Clojure utilizes non-standard Lisp syntax like []{}, weird function declaration and differ semantics of some forms (like cond usage, a powerful specie of switch-case of Lisp);
* Clojure don't have cons pairs, neither car and cdr operators. Cons pairs are fundamental Data Structures to build compound data, very well explored in SICP and any LISP text book.
* Clojure has the batteries of Java, so you will own a giant ecosystem to build complex software, but the evil parts of jvm will be inherited too. For the first contact with Lisp, this can be a unnecessary pain in the ass.
I would recommend to start a LISP journey with Land of Lisp or Practical Common Lisp (PCL), both focused in Common Lisp. Land of Lisp has a lot of history about the beginning of Lisp and the author write the book in a fun way, lot of charges and xkcd-like humor. The book has a collection of game projects per chapter, one at time, teaching principles of the language. PCL it's very useful for understanding specific parts of the language, I used as complement when Land of Lisp was not sufficient (loop topic on PCL is very good).
while Clojure is a Lisp with its own distinct flavor it gives you …
* a large community of practitioners and professionals (great for asking questions, finding collaborators, …)
* easy access to libraries in the js/jvm/.net ecosystems
* a style that relies more on data and transformations of data (illuminating simplicity)
in any case: it is worth digging deeper, one thing that kept me away was not knowing where to start (analysis paralysis). in hindsight picking any Lisp would have been great (instead of postponing).
Find a thread and start pulling :)
Rich Hickey’s talks were a great entry point for me https://github.com/tallesl/Rich-Hickey-fanclub
e.g. https://www.youtube.com/watch?v=rI8tNMsozo0 (the “Simplicity Matters” keynote at Rails Conf 2012)
edit: Land of Lisp is a great book as well
Yet, somehow out of all Lisp dialects, Clojure today remains the most pragmatic choice. Clojurescript is arguably the best alt-js choice, where Elm, Reason and Purescript for various reasons still can't reach its level of the simplicity and practicality.
Clojure has immutability by default, which alone has number of great benefits. It is FP focused. It can be learned à la carte, which greatly simplifies process of learning.
Clojure community is one of the friendliest and most diverse communities of developers.
In comparison, Common Lisp today (sadly) becoming like Latin of programming languages. It is cool to learn it and know it, but in many circles the practicality of that knowledge remains somewhat questionable.
The cons cell thing is a big deal. Cons cells are a stupid language construct. But that's baked into the identity of what Lisp is.
My own personal taste also leans towards Scheme (especially Chicken Scheme), so that's what I'd recommend. To me it feels more elegant, more modern, and of lighter weight than Common Lisp. I'm also kind of allergic to the JVM and Clojure's non-lispy innovations in syntax, so I'd personally avoid it too.
That said, I myself started with Common Lisp and then moved on to Scheme and then Emacs Lisp (which is a decent choice of Lisp to learn, in that, despite some shortcomings, it puts the entire Emacs ecosystem at your fingertips). Once I'd learned Common Lisp, I found learning the rest to be quite easy.
Sure it has some good concepts. But fanboys on internet make it seem like some God tier thing.
It was the first language to add "if/else" constructs, GC, closures, first class functions, reference semantics, and recursion.
It took between 5 to 40 years before these became available in mainstream languages (conditionals like if/else were adopted early, GC not so much, closures took even more). Add to that macros and the flexibility of runtime evaluation / code creation, which most mainstream languages still lack.
And of course, Lisp's rules remain (and will always be) the most succinct way to define a full blown programming language with meta-programming facilities to boot -- as opposed to a mere Turing machine like thing or assembler.
>IMO Lisp is just overrated, it lacks visual clues, reads right to left with horrible nesting etc..
This doesn't make any sense...
The nesting is the same as in almost any language.
"reads right to left" - huh?
You know that Lisp code can be indented right?
(second-fn (first-fn val))
(-> val first-fn second-fn)
How's this different than:
secondFn(firstFn(val))
val.firstFn().secondFn() var intermediaryVal = firstFn(val);
var result = secondFn(intermediaryVal); (let [intermediary-val (first-fn val)
result (second-fn intermediary-val)])
(-> val first-fn second-fn) (defn unique [str]
(->> (str/split str #"\s+")
(map #(Integer/parseInt %))
(partition-by even?)
(take-while #(not= (count %) 1))
(first)
(count)
(inc)))
(unique "2 4 6 8 7 10 12")
=> 5It usually looks likethis:
(cond (< a b) (println "a < b")
(> a b) (println "a > b")
:else (println "a = b"))
So this is just the same:
(cond (< a b) (println "a < b")
(> a b) (println "a > b")
:hotdog (println "a = b"))
There is an interesting situation is in the case family of constructs which match an input value against keys, in Common Lisp.
Inspired by cond, the t symbol also serves as the fallback in case when the key doesn't match the other cases. So that is to say:
(case (expr)
(a ...)
(b ...)
(42 ...)
(t ...)) ;; <-- this isn't matching on the t symbol!
But the programmer may also sometimes have the t symbol as a specific key value; or likewise the otherwise symbol. That requirement is handled by putting the key into a list:
(case (expr)
(a ...)
...
((t) ...)) ;; <- match on t f x | x < 0 = ...
| otherwise = ...
CL-USER 13 > (let ((a 1) (b 2))
(cond ((> a b) 'foo)
(:hello :there)))
:THERE
In earlier Lisp COND was the primitive and IF was a macro expanding into COND. In newer Lisp it's IF which is the primitive and COND which is the macro.
"Lisp is still #1 for key algorithmic techniques, such as recursion and condescension."
Parameter lists are wrapped in parenthesis and separated with commas, while code blocks are wrapped in curly braces and separated with semi-colons.
Lisp won't do this because it's then harder to blur/merge/change the distinction between code and data, which is the very power of Lisp.
Building architectural eyesores is probably not a rational plan for a city, but dammit, those eyesores help you know and remember where you are.
Some people have a certain kind of eye and/or brain that allows them to read Lisp quickly, but this may not be universal. Some say "with enough time you'll get used to it", but the fact Lisp has been around for 60 odd years without catching on in the mainstream is evidence of this. Somebody would be rich by now off its alleged advantages if they were real (beyond a "write-only" startup language).
Functional languages are better at expressing ideas but slower at communicating them to other readers, on average. I also personally find them difficult to debug because they don't have enough "intermediate state" to x-ray for debugging purposes. Here's a conceptual illustration:
// imperative:
a = af(param);
b = bf(a);
c = cf(b);
// functional
c = cf(bf(af(param)));
I'm convinced most of the people making jokes about parentheses or Lisp code being hard to read are superficially dismissing it without putting in even a minimal effort of working with it.
Things that don't immediately click are discarded. Individual curiosity ("Really smart people say great things about this, I wonder why that is..") leading to individual effort leading to deep understanding is not the prevailing attitude.
Sad state of affairs.
Often Lisp had been used as a teaching language for computer science concepts (recursion, evaluation models, algorithms, etc.) and thus it was associated by students with novel concepts they struggle with and not with solving practical problems. A typical example is the SICP book. It's great, but mostly CS and mathematics oriented -> the result is that the feedback is mixed.
Though it has tried a bunch of times.
> Some people have a certain kind of eye and/or brain that allows them to read Lisp quickly
Could be that or that one just needs a bit of practice - as it is the case with many thing: riding a bike, driving a car, learning a foreign language, mastering a new dance, ...
> 60 odd years without catching on in the mainstream is evidence of this
That you observe two things does not mean that they are necessarily in a causal relation.
> I also personally find them difficult to debug
One just introduces variables like in your imperative example:
(let* ((a (af param))
(b (bf a))
(c (cf b)))
c)
I haven't seen it done well. The attempts kind of end up with the worse of both worlds.
Re: Could be that or that one just needs a bit of practice
But the key is how much, and how long does it vary per individual. There is no solid research that I know of, so it's just opinion and anecdotes either way.
I tried to get used to it and read it fast, but it just felt progress was really slow. Most Algol-derived languages use punctuation and symbols that seem to make them stand out better than words alone. I'm not quite sure how to describe it, but standardizing the meaning of "funny symbols" help my particular eyes work faster. My head parses words too slow, and I have been reading words since kindergarten. Similar discussions:
https://wiki.c2.com/?LispLacksVisualCues
https://wiki.c2.com/?ChallengeSixLispVersionDiscussion
One can make that claim about any tool I should note, even COBOL. Some seasoned COBOLer's can crank out and read COBOL code really quick, I'd note. The top COBOLer can probably out-code an average Lisper I'd bet.
Re: That you observe two things does not mean that they are necessarily in a causal relation.
True, but per lack of formal studies per above, speculative observations are all any of us have. It should be a curiosity why after 60 years it never caught on mainstream. Almost nothing else in IT has had that many shots at it.
Re: One just introduces variables like in your imperative example:
Yes, but the Algol-derived languages (like C, Python, etc.) do that "style" in an easier-to-read and more consistent way, at least in my opinion.
Side note: why am I getting a rotten score? What did I do bad? I don't want bad scores. I'm just expressing my opinion openly. I don't feel I deserve punishment.
If we read a long novel, then we read mostly words without much visual structure. The only thing that guides us are occasional marks of sentences, paragraphs and chapters. Still many can read Lord of the Rings without much problem.
Lisp is slightly unusual, since the code is written as nested lists (trees). To make Lisp code readable there are a few things follow: speaking symbols, standardized code layout and familiar code structures. After a while the reader/writer of Lisp code will recognize the symbolic hints and the usual visual patterns of the layouted code.
> The top COBOLer can probably out-code an average Lisper I'd bet.
In terms of lines of code I would think that's true.
> It should be a curiosity why after 60 years it never caught on mainstream
Why should it be in the mainstream? Why should a programming language originally designed for certain types of meta-programming (remember: the symbolic computation and code as data ideas, which are central to Lisp) be especially popular among programmers and their customers?
> easier-to-read
Now you are shifting the goal. You originally claimed that functional code is hard to debug, because there are no variables you can inspect. But that's what we do in Lisp too: we use variables for that purpose.
Compared to what? I didn't say reading of Lisp comes to a stand-still, only that it's slower than block-type-indicator symbols. Maybe it is indeed possible to refactor written English for speed reading. I haven't surveyed the tests. Does anyone here want to claim English is optimized for quick reading?
It's kind of off topic, but I can envision using various symbols and block-markers to delineate parts of English sentences such as subject, verb, object, etc.: "(subject..) $verb {object...}" I think it would quicken MY reading, but I can't vouch for other humans. Maybe I'll patent it, or did Oracle beat me to it ;-)
But that's the idea: commonly occurring features are marked or surrounded with different symbols. You can't really do that in Lisp because nouns are verbs and verbs are nouns depending on the context/usage of the libraries or deeper code, while with Algol-derived languages mostly hard-wire the difference up front. You instantly know and don't have to stop and think or dig.
Indirection/abstraction can and does slow reading in many cases. I'm just the messenger. If YOU can read and process textual words fast, that's great but may NOT be universal across most humans.
> In terms of lines of code I would think that's true.
No, I meant features-per-hour, at least for business-oriented coding [in COBOL].
> Why should it be in the mainstream?
The standing implication, as I interpret it, is that functional programming is inherently superior in general, for a price of a slightly longer learning curve.
> Now you are shifting the goal. You originally claimed that functional code is hard to debug, because there are no variables you can inspect. But that's what we do in Lisp too: we use variables for that purpose.
I'm addressing TWO goals: easier-to-read and easier-to-debug.
> But that's what we do in Lisp too: we use variables for that purpose.
You add them just for debugging? Imperative style typically does that as in regular course. Thus, one doesn't have to alter the code as often just for debugging.
> After a while the reader/writer of Lisp code will recognize the symbolic hints and the usual visual patterns of the layouted code.
Indentation is not a difference maker in comparisons because both candidates can use it.
That's an assumption of yours.
> No, I meant features-per-hour, at least for business-oriented coding [in COBOL].
Another assumption, for which you assume justifications.
> The standing implication, as I interpret it, is that functional programming is inherently superior in general, for a price of a slightly longer learning curve.
I think of 'functional programming' as a tool. 'superior' is an attribute that you use.
Implication of what? 'functional programming'? Lisp is not 'functional programming'. Lisp in its root is a mix of full imperative programming (mutable variables + imperative control flow) with functional programming (first class functions, higher-order functions, ...).
> You add them just for debugging? Imperative style typically does that as in regular course.
Imperative code uses operators (which are functions) and functions.
a = 2 * b + 3 ^ b
c = 4 * a
r = c * pi * sin(a)
+, ^, sin, ... are basically functions. An operator is a function with an infix notation. Thus any imperative code which uses functions and operators is ALREADY a mix of imperative elements (mutable variables and imperative control flow) and calling functions.
In Lisp one might introduce the variables first and then set them:
(prog (a c r)
(setf a (+ (expt 3 b) (* 2 q)))
(setf c (* 4 a))
(setf r (* c pi (sin a)))
...)
(let ((a (+ (expr 3 b) (* 2 q)))
(c (* 4 a)))
(r (* c pi (sin a))))
...)
(flet ((e1 (b q)
(* (expr 3 b) (* 2 q)))
(e2 (a)
(* 4 a))
(e3 (c a)
(* c pi (sin a))))
(let* ((a (e1 b q))
(c (e2 a))
(r (e3 c a))
...)
Or I could write the code in some infix notation, since one can add infix syntax:
CL-USER 8 > (ql:quickload "infix")
To load "infix":
Load 1 ASDF system:
infix
; Loading "infix"
("infix")
CL-USER 9 > #I( a = 3 , b = 5 , c = a * b, c)
15
CL-USER 10 > #I( a = 3 ,
b = 5 ,
c = a * b,
c)
15
Every function introduces variables and LET / LET* are nothing else then binding constructs which are function calls:
(let ((a 10))
(* a 4))
((lambda (a) (* a 4)) ; anonymous function
10)
So when you think that one does use a strict functional and variable-free style of programming in Lisp, then this has no base in reality. Lisp is very much an imperative language.
> Indentation is not a difference maker in comparisons because both candidates can use it.
Layout of code is more than indentation.
So is the opposite viewpoint. Neither of us has a solid study that's directly relevant such that anecdotal info is all we have here either way. A good study would probably require millions of dollars. Yours is NOT the default position given the lack of such studies.
> Layout of code is more than indentation.
Same issue: both can do it so it's not a difference maker in comparisons.
> We can write Lisp code any way we want...one might introduce the variables first and then set them...or use LET*...or I could use local functions...etc...
But that's part of the "lack of standardization" that contributes to Lisp being more difficult to read. Standards and conventions are somewhat counter to "flexibility". We typically don't want overly-detailed standards (hard to remember) nor want excessive flexibility because then everybody and every spot may do things different.
There is an optimum balancing point in the standards vs. flexibility spectrum. Goldilocks. And the balancing point probably varies per individual.
> Yours is NOT the default position given the lack of such studies.
Your view would be more interesting to me if you'd have spent some time learning to read and write Lisp code. Much of what you claim is just guessing.
> Standards and conventions
There are standards and conventions in Lisp code. You just don't know them.
You are just guessing how difficult it might be to fly an airplane. It might be more difficult than a car, but how difficult it actually is not visible to you. You just guess that there are much fewer aircraft pilots than car drivers, and guess that flying a plane must be extremely difficult...
Same with you. It's not statistically safe to say that because some people do better with Lisp that everybody will given enough time. That doesn't tell us whether it's a personal fit or something more general.
Your line of reasoning appears to be "I did X and got result Y, therefore if everybody else does X, they will also likely get result Y". You hopefully should recognize the statistical fallacy in that pattern.
Anyhow, we are going in circles. There are no solid studies to back either of our viewpoints so we just have "anecdote fights" that don't get anywhere, which is quite common in Lisp-related debates. BeenThereDoneThat.
> There are standards and conventions in Lisp code. You just don't know them.
But they mostly rely on "parsing" words. I personally believe in the power of symbols. My eyes/head process most symbols much faster than words. I can't explain it, they just do. That's just my brain, although others have told me similar. If YOUR brain can process textual words as fast as symbols, that's wonderful, but may be specific to you (and other Lisp fans). Your head is NOT my head.
It's not like I'm new to words such that after reading a billion words I'll finally get better. People's textual reading usually plateaus after about 5 years as adults. Throwing time at the problem won't significantly change this. Why should Lisp be different? Words are words.
And sure there are standards/conventions in Lisp, but the competition also has standards/conventions such that it's not a difference maker in comparisons. The difference maker is WORDS alone versus words + symbols. (Well, Lisp has parentheses, but mostly only parentheses, unless you "invent" something custom, which makes it non-standard by definition.)
And I'm not against new things, but if they don't seem to be making sufficient progress after a reasonable amount of time, I abandon them. If Lisp is unique in that it has a hockey-stick shaped benefits curve (flat for long stretches, then goes up), then it stands out from most tools. It's hard to know if it has a weird learning curve up front since there are no decent studies on it. Often fans of tools claim "just try it long enough". That's not sufficient because it's a fan habit to claim that.
And structure.
> If YOUR brain can process textual words as fast as symbols, that's wonderful, but may be specific to you
Most people can do that. Most text people read just consists of words. Actually reading text with special symbols is quite complex - especially if the meaning depends on a mix of prefix, infix, postfix with different operator precedence.
> And sure there are standards/conventions in Lisp, but the competition also has standards/conventions such that it's not a difference maker in comparisons.
You claim a difference. I claim, you are just unfamiliar with Lisp.
> The difference maker is WORDS alone versus words + symbols.
No, the difference is words and structure.
Take for example the usual imperative code:
a := 3;
b := a*4;
if a > b
print a
else
print b
...
Lisp code would look like this:
(let* ((a 3)
(b (* a 4)))
(if (> a b)
(print a)
(print b)))
LET*
binding
binding
BODY
BODY
BODY
Lisp users learn to parse these visual and structural blocks & patterns. Once one has learned the vocabulary of basic code patterns, it's getting much easier to read Lisp.
They both have structure so it's not a difference maker in comparisons.
> Most people can do that. Most text people read just consists of words.
Yes, but "do" and "do better than alternatives" are different things. I already gave examples of possible alternatives/enhancements to typical English text that would help at least my brain. I won't reinvent that sub-discussion here.
> That's much more tree-like:
Being tree-like and being easier to read are not necessarily the same thing.
> I claim, you are just unfamiliar with Lisp.
How long do you believe it's realistic to keep at it if the benefits come slow? For example, if I keep coding in Lisp heavily for 2 years and STILL find it sluggish to read, is it realistic to then give up in your book?
> From that we can easily see that...
Who is this "we"?
I've been reading words and symbols for multiple decades in various contexts (programming, regular books, etc.). I've concluding after these decades that if used in the right spots, symbols GREATLY ENHANCE my ability to parse/grok/absorb written material IRREGARDLESS of the domain or the specific language.
For example, one thing I like from C# over VB.net is that C# uses square brackets for array indexes instead of parenthesis like VB does. It improved my head's groking speed of array-related code because parentheses have multiple meanings in VB. (I'm not claiming C# is overall better, this is just one aspect.)
Symbols MIXED with words (well) enhance the absorption of words. It's a ying-yang kind of thing. They COMPLIMENT each other. I truly doubt a billion years of using mostly just one OR the other will prove better than using them both.
Sorry, I believe Lisp is just plain lacking there. I want my ying-yang MTV. Go play your Wordy Gurdy in Jennifer's juniper garden.
Why not? structure can be different, example: shallow vers. deep. That both have some structure, that in both it's the same structure and that it is expressed in the same way.
> Being tree-like and being easier to read are not necessarily the same thing.
I did not claim that it is the same thing.
> How long do you believe it's realistic to keep at it if the benefits come slow?
You look for reasons not to learn it. You already KNOW that it will take years and will show no result.
> I've concluding after these decades
That makes little sense. After long and intense training lots of things look easy: juggling, flying a helicopter, ...
Unfortunately you haven programmed in Lisp and thus you have no idea about how difficult it would be to learn it.
I have also learned first to code in hex codes, assemblers, BASIC, Pascal, Modula, etc. Still I can read Lisp code just fine.
> I believe Lisp is just plain lacking there
You believe it, before even tried to learn Lisp and understand the difference.
You believe that a hammer is difficult to use, but you have only seen one, not hammered with it.
Your example implied it. If you meant something different, it wasn't explicitly stated. There are multiple factors that play into "easy to read", and they often differ per person. Tree-ness helps in some cases, but not others, or can be over-done.
> After long and intense training lots of things look easy
But reading words PLATEAUS in most people. You can't throw time at it to speed it up much. "Speed reading" courses don't improve comprehension of details, only summary skimming speed.
> I have also learned first to code in hex codes, assemblers, BASIC, Pascal, Modula, etc. Still I can read Lisp code just fine.
I'm not sure what point you are trying to make here.
> Unfortunately you haven programmed in Lisp and thus you have no idea about how difficult it would be to learn it.
I dabbled it in many years ago, and just found it hard to read and didn't see that exposure time was paying off in the speed compared to learning/reading other tools/languages. Groking it faster either has a long learning curve, or is the "hockey stick curve" I mentioned earlier.
You haven't explained why it has that comparatively slow ramp up and why I should accept the slow grok start compared to other tools. If it does have the hockey stick grok curve, it stands out unique in that regard and there should be a good reason behind that, yet strangely nobody knows why. You appear to be avoiding these key questions/puzzles. I don't understand why. If you want to promote Lisp, you better start caring about this decades-old conundrum: it's not going away. "Just keep it at forever" is NOT a good answer.
> You believe that a hammer is difficult to use, but you have only seen one, not hammered with it.
After many decades I have a pretty good feel for what kinds of tools, symbols, layouts, and UI's work best for MY eyes and brain. I'm not going to force things for 10+ years to see if my assessment rules of thumb are actually wrong for specific tools. That's not a rational use of anybody's time.
And MANY others have said the same about Lisp, and it has yet to catch on in the mainstream despite being around 60 years and tried in many projects. It does fine in certain niches and continues to do fine in those niches. But if you keep failing mainstream beauty pageants for 60 years, common sense should tell you that the public just plain finds you ugly. Get a clue already! Lisp has buck teeth and a big nose. You may have a thing for buck teeth, but your brain is not a representative specimen of humanity.
Further, there's nothing to force people to use good Lisp style and formatting. If it did go mainstream, more would probably abuse and misuse it. Fans treat their prized possession with care, others don't. Nice things that happen in Nicheville don't scale to big cities.
Sure you can, if you have an editor and REPL worth their salt. Select af(param)and evaluate it. There's what you're calling "a". Select bf(af(param) and evaluate it. There's what you're calling "b". How one carries out "select and evaluate" varies depending on the language, REPL, and editor in use, but there's almost always (always, in my experience) an easy way to do it.
Bonus: if it's a pure functional language (no side-effects) you can do it as many times as you like without messing anything up, and you didn't have to invent any otherwise-useless variables.
You clearly have no idea. Lisp has a REPL. True REPL. No, it's not a thing where you type something into it and it blurts out something in return like in most other languages. And it's better than so much praised Jupyter notebooks.
Lisp REPL is connected to your editor, and from your editor or IDE you can not only examine and evaluate any expression and sub-expression, you can do it on the fly, it gives you immediate feedback. You don't even need to think about a debugger (which Lisps do have too). You can try things while writing them.
Imagine a landscape artist that changes the entire landscape in real-time with every stroke of his brush. That's how it feels to be programming in a Lisp.
It sounds like one has to throw away years of "imperative habits" and just do everything different: reading, debugging, structuring, etc. For us non-Sheldons, it's hard to overhaul our head in a month.
Modern Lisps like Racket and Clojure are not that difficult to pick up. I think Clojure might be easier to learn than Python or Javascript. I'm serious.
Look, I understand the sentiment because I was on the same side relatively not too long ago. I never had a formal introduction into a Lisp. I thought Lisp is a dying language, something like Fortran, COBOL, or Pascal. On a whim, out of the blue, I tried learning it. I don't remember exactly why. I was bored or something. I started reading a book on Clojure. Then I found a conference that supposed to happen in a week. It was the first Clojure/Remote conf. I thought: "Well, it's remote. It's cheap. Let me try it out. What do I have to lose?" That conference has changed my life. Quite literally. I was fascinated by seeing awesome things people building. After the conf, I sat in my chair, staring into the void of my blank screen for several minutes. The next day, I went to the office and told them that I'm leaving. Without writing a single program in a language I did not know, I decided to find a job with a tech stack focused on Clojure.
There are lots of misconceptions circling Lisp. People look at Lisp code, and it just doesn't look "sexy" to them. And they immediately dismiss it, claiming it is hard to read. That's not true.
They say - it's dynamically typed mess. Without ever knowing that Clojure has a type system called Spec, which can do things, most other type systems cannot. There's a ton of research happening around type systems in Racket. "Little Typer" book teaches dependent types using a Lisp.
They say Lisp codebases don't scale - that's not true at all. The truth is - programming in Lisp makes people so productive, you don't need large teams to maintain a massive amount of work. And there are companies with large Lisp ecosystems, one example: NuBank in Brazil has over 400 engineers, and their primary language is Clojure.
People say Lisp is not popular. Sure, Clojure's popularity might look dwarfed in comparison with massively popular Python, Javascript, C++, Java, etc. However, Clojure, compared to other "esoteric" languages, is quite popular - today, it has more books, podcasts, conferences, and meetups. More than languages like Haskell, OCaml, Rust, Elm, Purescript, ReasonML, F#.
Learning Clojure has opened a world of possibilities for me personally. My only regret that I haven't gotten into Lisps earlier. Please, don't negatively take my advice. My intentions are sincere. I wish someone would've convinced me to try Lisp early in my career. Please, do sometimes try to get your head out of your shell and give it a try. I promise, if you give Lisp an honest and heartfelt try, you will find something unique. Even if you end up not using it, you will never regret learning it.
If we look at programming languages like Java, Typescript, C++, Haskell, etc., then we see that their type systems are completely different and have an entirely different purpose. Claiming to those users that spec is a type system, is just misleading them.
Lisp is based on math and logic. And if there's a God, he probably speaks Math. So, maybe those fanboys onto something here.
But, seriously, once you learn a bit of Lisp, you realize that Lisp has influenced every single modern programming language. Essentially, no matter what PL you are programming in - we are all programming in a Lisp. Sometimes your language of choice adheres to core principles of Lisp, sometimes that connection is loose. Nevertheless, there's plenty of Lisp in every modern programming language. So, no. Lisp is not overrated.
If I were given a choice to either hire five Javascript/Python/Go programmers and pay them each 100K/Y or hire only three Lispers and pay them each 200K/Y, I would go for the latter. ROI, in that case, would be much, much higher.
And Clojure is a very, very practical tool. Just watch Rich Hickey talks, you will see that the pragmatism of the language is paramount for everyone who uses it.
If that were universally true, one could out-compete the entrenched software companies and be the next Bill Gates. The common "production" languages are successful I believe because they offer a semi-consistent way to doing things, and for large or fungible staff, that turns out more important than less lines-of-code or powerful abstractions.
In business, communicating between humans is more important than parsimony. This is based on direct and indirect experience. My own "grand abstractions" have been rejected also at times. The "best" programmers are often those who have a decent understanding of the domain, UI design, and various "team" skills. Somebody good in all those may not necessary be the best abstractionist or parsimonist. The best programmers get B's on lots of topics rather than an A+ in just one, such as abstraction. I'm just the messenger. Scott Adams made a similar observation:
https://www.forbes.com/sites/carminegallo/2013/10/23/dilbert...
What makes a software product a successful product? Would you agree that popularity and sold copies do not necessarily make it the right product? There's a lot of marketing goes into success, and I admit - sound engineering often lacks good marketing.
What you can't see behind your clouded judgment that despite being non-mainstream tech, Clojure (I can only speak for Clojure since that's my primary language, I've been using for the past few years) has been quite successful.
- It is consistently being rated as the top paid language (alongside with F#) in numerous surveys (e.g., Stackoverflow and StateOfJS)
- The community has fewer active members than the number of programmers working for Google, but they are continually innovating. They are figuring out interop with Python and R, writing machine learning libraries and books about it, they are running Clojure-like Lisp dialect on BEAM, Clojure-like Lisp that compiles to Lua, researching type-systems, running Clojure on embedded devices, etc.
- Clojure teams at companies like Walmart and Apple processing massive amounts of data. Can you imagine the amount of data Walmart has to deal with on Black Fridays? Do you know how many people they have in the team that has built the pipeline for processing receipts? Seven. For comparison, React team at Facebook has more developers, and they also get massive help from it being open-source. I don't want to belittle the work they do; managing a massively popular UI library is not a simple task either. I just brought it here for the lack of better examples.
- Jira, incredibly popular and sometimes vehemently hated by programmers. Please take a look at its less popular competitive Clubhouse.io. It's beautiful, clean, and nothing but a fantastic product. I believe they've built it with a team of fewer than ten developers. And there are many examples like that: CircleCI, Grammarly, Pandora and many, many more.
I agree with what you say:
> The "best" programmers are often those who have a decent understanding of the domain, UI design, and various "team" skills.
That's why (after many years programming in other languages) I chose Clojure. It allows me to stay laser-focused on solving real problems. Like creator of Clojure once said: "solve real-world problems, not puzzles."
Yes, I already agreed it does well in certain niches. Usually in query-esque niches. SQL is also functional-esque for similar reasons.
You seem to be contradicting yourself, saying that other factors overwhelm FP's alleged programmer productivity gains, yet point out niches where it does well and is common. It spreads there, but not elsewhere.
> top paid language
I'll leave salary discussion to lispm's (user) reply thread.
> There's a lot of marketing goes into success, and I admit - sound engineering often lacks good marketing.
Yes, but that's mostly independent of programming productivity. It's not a difference maker in comparisons. Just because programming isn't everything to the bottom line doesn't mean it's nothing to it. For a software shop, programming is still a notable portion of activities that affect the bottom line. If you are 1% more profitable than your competitors, that difference will compound over time. If you grow 4% a year but your competitor grows just 3% a year, you'll eventually swamp them. Do a spreadsheet on it if you don't believe me.
means: developers are rare and too expensive. -> companies will avoid it.
Unlike other languages, Lisp sometimes is difficult to read by just looking at it. Staring at Lisp code, examining its "static" properties without prior training indeed may pose a challenge. But there is a way to learn how to parse Lisp code mentally. And the best way of learning that is by editing it.
First, you need to find an IDE that supports structural editing of symbolic expressions (or s-exps). Basically, it would help if you learned a few operations:
slurp, barf, transpose, raise, kill s-exp, yank s-exp
Depending on the IDE you use, they may be called differently, and there may be more, these are the basic ones.
Once you learn those basic operations, you are now ready to untangle "unreadable" Lisp. The trick is to change the code while you read it.
Similar to how Tony Stark looks at the hologram of a model and moves his hands outward, forcing the hologram to expand, then he picks one of the parts, studies it, maybe completely removes it. He then would move his hands in a closing motion, and hologram would "assemble." That's how you work with Lisp.
So, for example, you read a function, if necessary, extract things, pick an expression, evaluate it, etc. Once you gain a good understanding of what the function does, you can undo all the changes, or if you think you have improved it - do save.
In other languages, when the structure of the code is settled, it's more challenging to pick it apart, move things in and out. You are forced to read the code "top to bottom." But in Lisp, code is a living, breathing thing. You basically feel like performing a surgery - you can tweak things, try them, and see instantaneous feedback in the REPL.
In other languages, code is "dead," until you save it, (re)compile it and execute it. And REPL in those languages is "crippled" and not a fully-fledged "true" REPL like in Lisp. Being able to pick any [sub]expression and evaluate it, without any kind of prior ceremony is truly liberating and empowering.
It takes time, for some it's hours, for others - weeks, but eventually you will stop seeing parentheses, and instead, you will see structure, consistency, and meaning. And Lisp becomes more readable than any other language you've used before.
I'd like to see a university test this theory. I suspect it's subjective and varies greatly per individual, but testing on say 100 random subjects could better resolve the Great Lisp Dispute.
I don't know anything about music, but I feel this debate is like guitar tabs vs. standard music notation. I've heard, for example, that Paul McCartney doesn't know how to read music notation. "Yesterday" is still a masterpiece, though. Now imagine if Paul all his life advocated young musicians against musical notation, because "It's hard to learn to read it. And it's overrated."
The truth is - Lisp is fundamental and absolutely essential for anyone who chose a lifetime career in computer science. And it's not going anywhere, anytime soon. So please stop whining about it and at least get yourself familiar with it or stop calling yourself "a pro."
[Apologies for dramatization, the last part is not aimed at you personally. it's a general message for everyone.]