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There are no other homoiconic languages with amazing REPL support. After writing Lisp there is just something wrong about how most languages have an additional

There are no other homoiconic languages with amazing REPL support. After writing Lisp there is just something wrong about how most languages have an additional step in order to generate the AST. Why? A tree is a simple structure and describes the shape of code well. I can just write it myself. There is no reason to add weird arbitrary requirements on how you have to present your source code text to the compiler -- just feed it the data structure representing it instead. Since your code is just a tree now you can also write macros that are just functions. No text substitution or preprocessor jank. This is an amazing simplification and just feels as if it is the way it should be.

vegai_ 4y ago
>After writing Lisp there is just something wrong about how most languages have an additional step in order to generate the AST. Why? Because it's possible to have a lot better representations of computer code for humans than AST.
- medo-bear 4y ago
  some people really do find lisp to be the optimum and i say this as someone who works a lot in python i see lisp as similar to (all?) slavic languages, in which spelling is a trivial affair
  - eimrine 4y ago
    As someone who learns Common Lisp and speaks 2 slavic languages, I consider your statement as surprisingly legit.
    - deleted 4y ago
      [deleted]
- drewr 4y ago
  You underestimate the cognitive burden of resolving syntactic ambiguity with non-lisp languages. So many problems disappear with s-expressions that when I return to a language with a "human" syntax I feel bad that I have to work harder.
  - danuker 4y ago
    Indeed. In popular languages, I always add parens, because I'm second-guessing the parser. Lisps just embrace the parens :D
- yvdriess 4y ago
  Possibly, but I would argue we're not doing a very good job at that. Things like precedent rules plug into what we're used to for mathematical expressions, but that's only a small part of actual programming. Teaching novices without prior PL experience, you notice how much language syntax can get in the way, I get to the core concepts faster with scheme-driven classes than python-driven ones. Question to HN: have there been recent interesting empirical studies into the impact of PL syntax? I tend to always cite https://dl.acm.org/doi/10.1145/2534973 https://dl.acm.org/doi/10.1145/2534973 but newer ones might have superseded it.
- ctrlmeta 4y ago
  > Because it's possible to have a lot better representations of computer code for humans than AST. Which are those? I assure you I am a human and I find s-expressions to be clean, elegant, easy to read and easy to understand. I have learnt C, Java, C#, PHP, Perl, Ruby, Python, Go, Javascript, C++, Rust over the years and I have not found a syntax that feels better to me, the human. When I am writing tools for myself I reach out for Lisp because it is the most convenient one to write code in. I don't have to worry about all the syntactic ambiguities and complexities of these other languages. With Lisp, I can focus on solving my problem without being weighed down by complex syntaxes of other languages. You are saying there are better syntaxes out there? Where can I find this elusive language which has better representations of computer code for humans?
  - blep_ 4y ago
    A lot of this is pure preference, and if we try to debate the merits of prefix vs infix operators we're just going to yell MY PREFERENCES ARE RIGHT AND YOURS AREN'T at each other until we get bored. But there are some places where I think Lisp syntax is objectively worse than the alternatives. Parsing Lisp is easy because it shifts all the hard parts to the semantic layer. Everything looks so similar that you have to do a lot more reading, and memorization, to know what's going on at all. ---- To take a supposedly good example from elsewhere in this thread[0]: > (do-a-thing b (+ a 5)) Is this a function call, or a thing that expands into something totally different? It matters, because (+ a 5) may not be something so trivial - it may have side effects, or be evalulated multiple times. (If it was a lazily evaluated pure function, there would arguably be no point to having macros at all.) This one is trivially solvable by making macros visually distinct in some way, e.g. Rust's ! suffix, or C's convention of MACROS_YELLING_AT_YOU. It doesn't matter what the syntax is, as long as it exists. ---- Is (progn a b c) a function call or a special form? What about (proxy a b c) or (pregen a b c), both totally plausible names for functions? It's totally possible, even easy, to tell those things apart if you're paying attention, but you have to actually read the word at the start and comprehend it. In languages with dedicated syntax for this, you can just recognize { and } and instantly know what's going on, no need to involve the word-recognition parts of your brain at all. This sounds trivial - nearly all syntax decisions are - but it adds up when everything in the language is like this. ---- [0] https://news.ycombinator.com/item?id=33469932 https://news.ycombinator.com/item?id=33469932; I've renamed the macro here to make my point clearer, because the obvious response would be "well obviously someMacro is a macro", but in the real world people do not name their macros that.
rscho 4y ago
> There are no other homoiconic languages with amazing REPL support Prolog is pretty good.
- pjmlp 4y ago
  And unfortunely with the same amount of commercial support as Lisp languages.
  - eimrine 4y ago
    As much of commercial support as Pythagoras theorem.
- dj_mc_merlin 4y ago
  Touché. Excuse my ignorance, feel free to correct me, but I've always viewed Prolog as suited to specific tasks, whereas Lisps are more general purpose. There's games in Lisp for example, not a lot, not all of them great, but they're still there. I'm not aware of any Prolog games. SBCL is also within 2x-4x of C quite a lot so unless you really need every last bit of performance you're fine, as opposed to Prolog's snail-like tendencies. Static typing and turning off safety checks/turning on optimizations can get you very close to as fast as you'll ever need.
  - rscho 4y ago
    Prolog is probably less of a general-purpose language, in the sense that writing things such as games are probably not a very suitable goal for it. But for any problem involving the exploration of a solution space, prolog is absolutely stellar and actually quite fast, and even faster to write: solvers, irregular data processing, symbolic reasoning... It also lends itself quite well to "I just want to query a database" apps, including websites. Have a look at the "power of prolog" YouTube channel if you are interested.
deterministic 4y ago
> There are no other homoiconic languages with amazing REPL support. True but nobody outside of the Lisp community cares. Not trolling just stating a fact.
- medo-bear 4y ago
  given that you frequent lisp related topics on hn i would say you care more than you let on
  - mbrodersen 4y ago
    Yep. But it’s more the LISP community that is fascinating to me than the LISP language :)
    - lispm 4y ago
      must be, you are posting the same message since a few years.
      - medo-bear 4y ago
        pretty sad actually

vegai_ 4y ago

>After writing Lisp there is just something wrong about how most languages have an additional step in order to generate the AST. Why? Because it's possible to have a lot better representations of computer code for humans than AST.

medo-bear 4y ago
some people really do find lisp to be the optimum and i say this as someone who works a lot in python i see lisp as similar to (all?) slavic languages, in which spelling is a trivial affair
- eimrine 4y ago
  As someone who learns Common Lisp and speaks 2 slavic languages, I consider your statement as surprisingly legit.
  - deleted 4y ago
    [deleted]
drewr 4y ago
You underestimate the cognitive burden of resolving syntactic ambiguity with non-lisp languages. So many problems disappear with s-expressions that when I return to a language with a "human" syntax I feel bad that I have to work harder.
- danuker 4y ago
  Indeed. In popular languages, I always add parens, because I'm second-guessing the parser. Lisps just embrace the parens :D
yvdriess 4y ago
Possibly, but I would argue we're not doing a very good job at that. Things like precedent rules plug into what we're used to for mathematical expressions, but that's only a small part of actual programming. Teaching novices without prior PL experience, you notice how much language syntax can get in the way, I get to the core concepts faster with scheme-driven classes than python-driven ones. Question to HN: have there been recent interesting empirical studies into the impact of PL syntax? I tend to always cite https://dl.acm.org/doi/10.1145/2534973 https://dl.acm.org/doi/10.1145/2534973 but newer ones might have superseded it.
ctrlmeta 4y ago
> Because it's possible to have a lot better representations of computer code for humans than AST. Which are those? I assure you I am a human and I find s-expressions to be clean, elegant, easy to read and easy to understand. I have learnt C, Java, C#, PHP, Perl, Ruby, Python, Go, Javascript, C++, Rust over the years and I have not found a syntax that feels better to me, the human. When I am writing tools for myself I reach out for Lisp because it is the most convenient one to write code in. I don't have to worry about all the syntactic ambiguities and complexities of these other languages. With Lisp, I can focus on solving my problem without being weighed down by complex syntaxes of other languages. You are saying there are better syntaxes out there? Where can I find this elusive language which has better representations of computer code for humans?
- blep_ 4y ago
  A lot of this is pure preference, and if we try to debate the merits of prefix vs infix operators we're just going to yell MY PREFERENCES ARE RIGHT AND YOURS AREN'T at each other until we get bored. But there are some places where I think Lisp syntax is objectively worse than the alternatives. Parsing Lisp is easy because it shifts all the hard parts to the semantic layer. Everything looks so similar that you have to do a lot more reading, and memorization, to know what's going on at all. ---- To take a supposedly good example from elsewhere in this thread[0]: > (do-a-thing b (+ a 5)) Is this a function call, or a thing that expands into something totally different? It matters, because (+ a 5) may not be something so trivial - it may have side effects, or be evalulated multiple times. (If it was a lazily evaluated pure function, there would arguably be no point to having macros at all.) This one is trivially solvable by making macros visually distinct in some way, e.g. Rust's ! suffix, or C's convention of MACROS_YELLING_AT_YOU. It doesn't matter what the syntax is, as long as it exists. ---- Is (progn a b c) a function call or a special form? What about (proxy a b c) or (pregen a b c), both totally plausible names for functions? It's totally possible, even easy, to tell those things apart if you're paying attention, but you have to actually read the word at the start and comprehend it. In languages with dedicated syntax for this, you can just recognize { and } and instantly know what's going on, no need to involve the word-recognition parts of your brain at all. This sounds trivial - nearly all syntax decisions are - but it adds up when everything in the language is like this. ---- [0] https://news.ycombinator.com/item?id=33469932 https://news.ycombinator.com/item?id=33469932; I've renamed the macro here to make my point clearer, because the obvious response would be "well obviously someMacro is a macro", but in the real world people do not name their macros that.

rscho 4y ago

> There are no other homoiconic languages with amazing REPL support Prolog is pretty good.

pjmlp 4y ago
And unfortunely with the same amount of commercial support as Lisp languages.
- eimrine 4y ago
  As much of commercial support as Pythagoras theorem.
dj_mc_merlin 4y ago
Touché. Excuse my ignorance, feel free to correct me, but I've always viewed Prolog as suited to specific tasks, whereas Lisps are more general purpose. There's games in Lisp for example, not a lot, not all of them great, but they're still there. I'm not aware of any Prolog games. SBCL is also within 2x-4x of C quite a lot so unless you really need every last bit of performance you're fine, as opposed to Prolog's snail-like tendencies. Static typing and turning off safety checks/turning on optimizations can get you very close to as fast as you'll ever need.
- rscho 4y ago
  Prolog is probably less of a general-purpose language, in the sense that writing things such as games are probably not a very suitable goal for it. But for any problem involving the exploration of a solution space, prolog is absolutely stellar and actually quite fast, and even faster to write: solvers, irregular data processing, symbolic reasoning... It also lends itself quite well to "I just want to query a database" apps, including websites. Have a look at the "power of prolog" YouTube channel if you are interested.

deterministic 4y ago

> There are no other homoiconic languages with amazing REPL support. True but nobody outside of the Lisp community cares. Not trolling just stating a fact.

medo-bear 4y ago
given that you frequent lisp related topics on hn i would say you care more than you let on
- mbrodersen 4y ago
  Yep. But it’s more the LISP community that is fascinating to me than the LISP language :)
  - lispm 4y ago
    must be, you are posting the same message since a few years.
    - medo-bear 4y ago
      pretty sad actually