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Comment by szopa | Hacker News Reader

Why should we be excited about this?

It's an implementation of an ISO-standardised Lisp, pretty much a cleaned up and streamlined ISO alternative to ANSI Common Lisp and the Scheme:s. Aims to be industrially relevant rather than academic, the object system is somewhat simpler than CLOS. More here: http://islisp.org/

The GraalVM is a tool used, among other things, to produce native binaries, and Truffle a programming language for implementing programming languages on Graal.

One could expect pretty good performance, possibly at the price of somewhat slow compilation.

Which doesn't have macros nor hash table according to http://www.islisp.org/whatisISLisp.html

Good joke.

ISLisp has macros. (I'm looking at section 16 of the latest 2007 working draft.)

Hmmm, then did I misread this fragment?

"In ISLisp, language specifications are separated from processor specifications. ISLisp forms after macro expansion and other pre-processing are called "prepared form" and ISLisp does not define preparation procedures."

http://islisp.org/docs/islisp-v23.pdf , page 61-62. Has a familiar defmacro, with quote/unquote/quasiquote.

The text you're quoting implies the language has a macro expander. There are arrays and vectors, so you could implement hashmaps, and I think some of the implementations of the language already does.

That exact text is not found in the spec; it's from the ISLisp page. ISLisp does have the concept of "prepared form" it refers to, but you have to look at the spec to understand what that means.

It looks to me that this "prepared form" is the same as in other traditional Lisps: that the source code of the program is defined in terms of nested lists, but may undergo a transformation into an undocumented form (for instance ARM machine language) in preparation for execution. E.g. in Steel Bank Common Lisp, everything you type into the REPL is first transformed into machine code and then run. Common Lisp doesn't define the details of such a thing, but does have a lot to say about compilation.

The actual ISLisp says:

An object is prepared for execution; this might include transformation or compilation, including macro expansion. The method of preparation for execution and its result are not defined in this document (with exception of the violations to be detected). After successful preparation for execution the result is ready for execution.

Obviously, the macro expansion parts are defined at least to some extent because it interacts with user macro definitions. (Perhaps even when it comes to macro expansion, ISLisp doesn't nail down the exact semantics, like when exactly is it done. It's possible for a pure Lisp interpreter to work with unexpanded code and continuously re-expand any macro call that it encounters, in the latest dynamic environment. That allows for macros to be fixed on-the-fly.)

But on the very linked page it says:

    ISLISP, a spiritually CommonLisp-lite:

        Adhoc polymorphism through generic methods;
        Dynamic and lexical scoping;
        Procedural macros.

Judging by the name, the exciting part is the framework it was written on. As a habit, I do not use software that relies on code association in the name as a selling point. A lot of new coders use this naming convention, as they've become excited cheerleaders for their platform of choice (especially if it is a recent language or framework). But how much do actual users care about the underlying technicals? Why make the software sound like it is part of the language or framework when it isn't?

Imagine if there was an InlineAsmGrub to compete against that other GRUB. It's just that silly a practice.

I see where you're coming from, and the naming was quite unimaginative, indeed. I saw that "truffle ruby" called itself that and copied it.

However, the fact it's based on truffle is the selling point -- truffle enables interop between languages on the framework. So, for example, you can take truffle JS implementation, import express library or whatever, and then as part of the implementation do

````

let fn = Polyglot.eval('islisp', '(lambda (x) (+ x 1))');

fn(1);

````

(toy example. But this interop can happen in all directions, it's not limited to js but can be used from truffle python, ruby, java, etc; and it also isn't limited to just primitive values, you can pass around functions as well).

If you aren't looking for a specifically a truffle lisp, it would make more sense to use one of the established common lisp implementations.

I think the name is good. It took me a whole second to figure out its selling point, especially since there is a new "lisp" being made every day. Fancy names are exciting for like a millisecond. Good luck with the project! Im a Common Lisp user but this seems like a plausible alternative to Clojure and even ABCL

When building an alternative implementation of a language you're a bit hamstrung by the name. You could come up with something completely novel, but no one is ever going to discover or use your software. So, it's quite common to integrate the language name into your software name somewhere. The next question then is how to differentiate. Oftentimes the underlying framework is really the selling point. JRuby is Ruby on Java. TruffleRuby is Ruby on Truffle+Graal. It's easy for people to quickly identify and understand the difference. Instead of calling it TruffleRuby, I suppose we could call it PartialEvaluationRuby or SuperFastRuby, but those naming conventions have their own flaws.

Do you have a suggested naming convention to follow? There's a rich history of alternative language implementations following the convention you dislike, but I think those involved would be open to an alternative.

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