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by vatsachak6 hours ago |
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upvoteby so-cal-schemer1 hours ago|
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Lisp/Scheme/Racket is a very simple language that is also very fluid and malleable. You can express ideas and computations very precisely, concisely, and intuitively. There really aren't any barriers as they (Scheme/Racket at least) are rooted in the Lambda Calculus which is a theoretical model equivalent to the Turing Machine. Any language feature you'd like can be expressed: Want standard infix math expressions or a borrow-checker? That's a macro. Want lazy evaluation? That's a simple change in a meta-circular evaluator. Want a language that is the simplest and most direct mapping to your problem domain? A DSL.

The syntax lends itself to easy structural editing way before LSPs..

Why Racket? Why Lisp?

https://beautifulracket.com/appendix/why-racket-why-lisp.htm...

Why language-oriented programming? Why Racket?

https://beautifulracket.com/appendix/why-lop-why-racket.html

Creating Languages in Racket: Sometimes you just have to make a better mousetrap.

https://queue.acm.org/detail.cfm?id=2068896

Lisp is clay: the power of composable DSLs

https://fosdem.org/2026/schedule/event/HDE7JZ-lisp-is-clay/

The other powers of Lisps (interactive development, hot reloadability, restarts on error, etc) are more tied to the sophistication of their implementations and runtime environments.

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upvoteby 2 hours ago|
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upvoteby WalterGR6 hours ago|
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Homoiconicity.
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upvoteby chowells5 hours ago|
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What makes this a desirable feature? From the perspective where local reasoning is the most desirable property a language can have, how does homoiconicity support that?

I honestly am curious. I've seen a few examples presented for it, but they always seem like bad software engineering to me. Where's an example that does something in a cleaner way than alternatives present in other languages while remaining compatible with local reasoning?

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upvoteby gus_massa3 hours ago|
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Homoiconicity makes writing macros easy.

If you don't like it, you can try https://rhombus-lang.org/ that is build on Racket and also has macros but uses a Python-like syntax.

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upvoteby Zambyte1 hours ago|
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Easy is an understatement. Macros and dynamic programming (often done using runtime reflection in other languages) are so trivially easy in Lisps that one can stumble into it without realizing they're even doing it. Anyone who has done these things in more "modern" languages knows these features are not something one can accidentally start doing. They take a lot of deliberate effort relative to standard, static programming.
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upvoteby soegaard1 hours ago|
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> Easy is an understatement. Macros and dynamic programming (often done using runtime reflection in other languages) are so trivially easy in Lisps that one can stumble into it without realizing they're even doing it.

Well, getting the interaction between modules and syntax transformations (macros) right is not an easy task.

"Composable and Compilable Macros: You Want it When?" Matthew Flatt http://dl.acm.org/authorize?24908

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upvoteby WalterGR4 hours ago|
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> From the perspective where local reasoning is the most desirable property a language can have

That's a perspective. If you're looking for a low-level language, then Scheme isn't it. (Forget iconicity - Scheme is garbage-collected. And supports continuations!)

If you don't program in machine code - which would maximize local reasoning - then you must know the language with the Correct balance of local reasoning and higher-level constructs. Knowing which language that is would add specificity to this discussion...

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upvoteby so-cal-schemer51 minutes ago|
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https://prescheme.org/

Pre-Scheme is a statically typed dialect of the Scheme programming language, combining the flexibility of Scheme with the efficiency and low-level machine access of C. The compiler uses type inference, partial evaluation, and other correctness-preserving transformations to compile a subset of Scheme into C with no additional runtime overhead. This makes Pre-Scheme a viable alternative to C for programming virtual machines, operating systems, and embedded systems where the runtime overhead of a complete Scheme implementation is not desirable.

https://ryansuchocki.github.io/microscheme/

Microscheme, or (ms) for short, is a functional programming language for the Arduino, and for Atmel 8-bit AVR microcontrollers in general. Microscheme is a subset of Scheme, in the sense that every valid (ms) program is also a valid Scheme program (with the exception of Arduino hardware-specific primitives). The (ms) compiler performs function inlining, and features an aggressive tree-shaker, eliminating unused top-level definitions. Microscheme has a robust FFI (Foreign Function Interface) meaning that C code may be invoked directly from (ms) programs. Therefore, the power of the existing wealth of Arduino libraries is available within Microscheme.

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upvoteby WalterGR2 minutes ago|
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Fair point.
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upvoteby chowells1 hours ago|
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That's not at all what local reasoning means. Local reasoning is the property that a piece of code contains (when including the call graph) everything that can affect what it does. All mutation of a value is kept within some scope of ownership of that value. If you want to understand a piece of code, you can do it by understanding that piece of code, not the program as a whole.

Assembly makes non-local reasoning mandatory, as any code can update any location in memory without restriction. All memory accesses are global. References need not even be by name - they can be via computed addresses. There are no restrictions in place allowing the structure of the program to provide boundaries on what pieces of code may be understood as units.

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upvoteby so-cal-schemer23 minutes ago|
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Homoiconicity is orthogonal to local reasoning. It just means the syntax is represented by the native data format, nested lists. This does make code generation very straightforward with list processing primitives.

Mutation in scheme is possible, via set!, and set-car! and set-cdr!, but it's not recommended. Functional program design side-steps the issue.

see also:

SICP: 3.1.3 The Costs of Introducing Assignment

https://sarabander.github.io/sicp/html/3_002e1.xhtml#g_t3_00...

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upvoteby bjoli4 hours ago|
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it allows you to create a language that compiles to your original language.

You can abstract everything away. Not like Haskell where laziness accounts for some and typeclasses for some (and often an exponential growth in compile times). No, it property let's you change the language.

I got tired of loops sucking and made this, for example: https://rikspucko.koketteriet.se/bjoli/goof-loop

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upvoteby chowells4 hours ago|
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This doesn't strike me as better than the alternatives. In Haskell, it's just a few different functions to handle the different use cases. That strikes me as far better than one "function" that magically does different things depending on how it's called. It is local, I'll give you that. But it still seems bad because you have overloaded the semantics along multiple axes simultaneously. I prefer building blocks with only a single set of semantics each. I believe it's better to write precise code than DWIM code.
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upvoteby eru2 hours ago|
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C has homoiconicity: you can represent C source code as C strings.
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upvoteby Zambyte1 hours ago|
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You can't natively index into a string and get any C syntactic token out of it besides a char.
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upvoteby jibal1 hours ago|
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You can't run that code within the language so no, obviously not. And even if you could, strings + eval alone is not homoiconicity--programs are not manipulated by the compiler as unstructured text strings.
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upvoteby layer84 hours ago|
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I don’t find it appealing when everything looks the same irrespective of purpose and context.
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upvoteby BoingBoomTschak11 minutes ago|
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You can read the words, you know? Together with proper indentation that almost makes it look like Python, there's no way you can get lost in Lisp.
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upvoteby eru2 hours ago|
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Seems like a non-sequitur.
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upvoteby layer82 hours ago|
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How so? Homoiconicity means that everything uses the same form of representation, and I’m familiar with how these things look in Lisp.
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upvoteby jibal1 hours ago|
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Does i + 1 look the same as "i + 1"? The first is an expression, the second is a string. In LISP, it's similarly (+ i 1) vs '(+ i 1).

These sorts of shallow complaints can be made of any feature than one is not familiar with, hasn't used, and doesn't know or understand the benefits of. In any case, no one is forcing people to use this language or take advantage of this feature.

P.S. The "response" actually ignores all points made, attacks strawmen, moves the goalposts, and is intellectually dishonest (the original comment was clearly a complaint, and besides it wouldn't matter if some other word like "criticism" or "dissatisfaction" were substituted--my point remains). Again, no one is forcing anyone.

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upvoteby layer81 hours ago|
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To answer your question, yes it does look pretty much the same in the Lisp version, less so in the string version. Also I didn’t complain; I expressed the opinion that I don’t agree that homoiconicity increases the appeal of a programming language, because the drawbacks outweigh the possible benefits for me. I spent some time programming in Lisp and am familiar with how homoiconicity works there.

The point is that these things are subjective, and there will never be a programming language that everyone likes the best.

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