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Why Fennel?

fennel-lang.org

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Re: Why Fennel?

#81

Post by satvikpendem »

caddzooks wrote: post #79
torginus wrote: post #43

I do not understand the appeal of LISPy languages. I get that the parser is simple and elegant, but I believe the developer (of the compiler in this case) should serve the convenience of the user, not the other way around. Writing code like this is cumbersome and unnecessarily symbol heavy, and reading it isn't really nice as well. I'd rather have the language add that extra complexity into the parser than have me st…

Consider the following LISP function that performs a transformation of an MxN matrix: (defun transpose (matrix) (apply #'mapcar #'list matrix)) Based on my own experience I think I can say that It isn't until one has acquired a reasonable amount of experience with the language that they can fully appreciate its power.

Now try it with BQN

Re: Why Fennel?

#82

Post by akoboldfrying »

I'm a bit puzzled by whether Fennel is trying to make "different things look different" as they claim, or not. On the one hand, Fennel separates Lua's multipurpose "for" into "for" (for numeric ranges) and "each" (for iterators). On the other hand... Don't macros and function calls, two rather different things with different powers, look identical in Fennel?

On the "Values" page, they also mention a macro that alters the lexical scope somehow. This macro is now deprecated, but its mere existence implies that such a macro can be expressed in Fennel -- that is, that it's possible to write Fennel code that causes what looks like an ordinary function call to do surprising things to the program state.

As they rightly mention (on either this page or the "Values of Fennel" page), the advantage of constraining a language is that you can more easily tell what a program is doing (and not doing) at a glance. But this seems to be undone by giving a pass to (unhygienic?) macros.

Re: Why Fennel?

#83

Post by z5h »

Ok I’m genuinely convinced I’d be happier using Fennel than using Lua in instances where I need to use Lua. I’m not currently using Lua for anything. Maybe if I write a Pico-8 app…

Re: Why Fennel?

#84

Post by smnplk »

NewsaHackO wrote: post #56
n4ture wrote: post #45

Earlier quoted context omitted.

I do not understand the appeal of non-LISPy languages. I get that most people are used to reading it and that they are efficent, but I believe the developer (of the compiler in this case) should serve the convenience of the user, not the other way around. Writing code like this is combersome and unnecessarily symbol heavy, and reading it isn't really nice as well. I'd rather have the language add those extra parens i…

This doesn't really resonate with people though, as most people are more familiar with C-style notation. Also: >Writing code like this is combersome and unnecessarily symbol heavy Does not make sense in this context, as it mainly applies to Lisp-like languages that uses parentheses heavily.

>> as it mainly applies to Lisp-like languages that uses parentheses heavily.

This is so wrong. Lisp does not use parentheses heavily. It doesent even use more parens than any C like language. I just dont understand the fixation with parentheses. The power of lisps comes from the fact that everything is an expression. Someone can correct me if I am wrong, since I only have experience with functional lisp Clojure, but I believe other lisps are more or less similar.

So if everything can be evaluated, then you can have a really great REPL experience. You can be inside your favorite editor and have the tightest feedback loop possible. So the absence of statements is actually a great feature of the language which improves ergonomics.

Re: Why Fennel?

#85

Post by evdubs »

torginus wrote: post #43

I do not understand the appeal of LISPy languages. I get that the parser is simple and elegant, but I believe the developer (of the compiler in this case) should serve the convenience of the user, not the other way around. Writing code like this is cumbersome and unnecessarily symbol heavy, and reading it isn't really nice as well. I'd rather have the language add that extra complexity into the parser than have me st…

Try defining data in C. Try extracting data from that data you've defined in C.

If you can understand the appeal of having JSON in JavaScript, you can understand some of the appeal of Lisp.

Re: Why Fennel?

#86

Post by shakna »

torginus wrote: post #43

I do not understand the appeal of LISPy languages. I get that the parser is simple and elegant, but I believe the developer (of the compiler in this case) should serve the convenience of the user, not the other way around. Writing code like this is cumbersome and unnecessarily symbol heavy, and reading it isn't really nice as well. I'd rather have the language add that extra complexity into the parser than have me st…

Most Lisp-y language have multiple parsers. The frontend may be that one, or it might be another. Racket has hundreds of frontends [2], Scheme has Wisp [0], and so on.

The ideal part of it comes down to the language being able to manipulate itself. Make the tokens an array, that you can shift, inject and/or mould into what you need.

That being said, that power isn't isolated to just Lisp-y. A few stack languages have it, like Forth, or to plug myself [1]. However, stack languages are a bit harder to optimise.

It isn't that they don't want a complicated parser. It's that you want to be able to easily modify that parser as its running, without hitting TeX levels of performance slowdowns.

[0] https://srfi.schemers.org/srfi-119/srfi-119.html

[1] https://git.sr.ht/~shakna/jstack

[2] https://doi.org/10.1145/3580417

Re: Why Fennel?

#87

Post by Vegenoid »

evdubs wrote: post #85
torginus wrote: post #43

I do not understand the appeal of LISPy languages. I get that the parser is simple and elegant, but I believe the developer (of the compiler in this case) should serve the convenience of the user, not the other way around. Writing code like this is cumbersome and unnecessarily symbol heavy, and reading it isn't really nice as well. I'd rather have the language add that extra complexity into the parser than have me st…

Try defining data in C. Try extracting data from that data you've defined in C. If you can understand the appeal of having JSON in JavaScript, you can understand some of the appeal of Lisp.

I’m having trouble understanding what you mean, if you could provide or link to an example I’d appreciate it.

Re: Why Fennel?

#88

Post by zelphirkalt »

smnplk wrote: post #84
NewsaHackO wrote: post #56

Earlier quoted context omitted.

This doesn't really resonate with people though, as most people are more familiar with C-style notation. Also: >Writing code like this is combersome and unnecessarily symbol heavy Does not make sense in this context, as it mainly applies to Lisp-like languages that uses parentheses heavily.

>> as it mainly applies to Lisp-like languages that uses parentheses heavily. This is so wrong. Lisp does not use parentheses heavily. It doesent even use more parens than any C like language. I just dont understand the fixation with parentheses. The power of lisps comes from the fact that everything is an expression. Someone can correct me if I am wrong, since I only have experience with functional lisp Clojure, but…

The anti parentheses argument is usually just a straw that people grasp, who have no experience with writing code in lispy languages. A quick superficial jab at something they do not know well, so that they can go on with their day, without having to deal with learning a new thing, that might change their whole view of programming.

Re: Why Fennel?

#89

Post by zelphirkalt »

Guvante wrote: post #77
n4ture wrote: post #45

Earlier quoted context omitted.

I do not understand the appeal of non-LISPy languages. I get that most people are used to reading it and that they are efficent, but I believe the developer (of the compiler in this case) should serve the convenience of the user, not the other way around. Writing code like this is combersome and unnecessarily symbol heavy, and reading it isn't really nice as well. I'd rather have the language add those extra parens i…

Let's be real in most situations it doesn't matter. One "statement" per line is bog standard. Whether that statement is surrounded by parens or ended in a semicolon isn't impactful for reading. LISP is only better when you add source code transformation (which is way easier with its source code looking like the transformed code). But then you introduce "everyone can write their own syntax" which is good and bad given…

When writing code you are transforming it all the time. Having only expressions (mostly) comes in very handily. It is called structured editing of code.

Re: Why Fennel?

#90

Post by frogulis »

duncanfwalker wrote: post #31

The comparison with Closure is really interesting. They make the point that they do less reinvention of Lua than Closure does with Java - functions, standard library, tooling. I'd love to know why. Is it just that Lua has less problems than old-Java

I get the impression that Fennel is intended as a different/better interface for Lua.

In contrast, Clojure is intended as the language Rich Hickey wanted for writing the sort of applications he wrote, and the JVM happened to be a powerful (and already existing) platform that was suitable for doing that.

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