3 ms·

This is rather tricky subject - to understand real behavior - what is behind this or that a syntactic sugar. In Scheme, for example, we could implement any dat

This is rather tricky subject - to understand real behavior - what is behind this or that a syntactic sugar. In Scheme, for example, we could implement any data-structure as a closure, which accepts messages. There is no difficulty in writing such wrappers - it is just a closure which return another closure which accepts "messages", and following some protocol, returns, for example, another closures to be called for a certain action (generators, iterators, etc.) We could teach the read function to recognize any kind of wired syntax we wish, and constructing appropriate data-structures with type-tags attached to them. But it will become a mess. The real data-structures, however, its representation is very different thing. In Clojure, I suppose, it is based on built-in Java types and generic interfaces, such as Iterable or whatever it is. So, they are ordinary Java objects, without any magic in it. In Scheme or CL it depends on the implementation, the choices made by developers. So, for example, Gambit-C and MIT Scheme are quite different in how they implement hash-tables or vectors. My guess is that, say Alegro CL and CMUCL are also very different, yet they all conform to some standards (CLtL2, ANSI). Having very different implementations with different set of compromises is a strength. So, in my opinion, there is absolutely nothing special in this syntactic constructions, moreover, it is not that difficult to implement them using closures and macroses. In arc.arc you could see how strings and tables were implemented. Another issue is, should we add all this wired syntax to what we call Lisp? In my opinion doing this ruins Lisp and the result is some very different in a look-and-feel language. Calling it Lisp is, well, confusing, at least to me. Arc is a Lisp, no doubt. CL and Scheme are Lisps, for sure. Clojure is Java with lisp-like syntax, if you wish.) The old rules says that there must be very heavy reasons to add any new symbol or a keyword into a language, and that the same things shall look the same, and different - differently. For me, personally, Arc is a proper approach, while Clojure is, well, a mess.)

chongli 14y ago
>So, in my opinion, there is absolutely nothing special in this syntactic constructions, moreover, it is not that difficult to implement them using closures and macroses. In arc.arc you could see how strings and tables were implemented. You're right, there is nothing special about what Clojure does; everything could be implemented in Scheme just fine. The real advantage comes from the fact that these things are there "out of the box" so that libraries are written to use them. There is a lot of inertia when it comes to libraries in a language. In some sense, you only get one chance to get it "right" before everything becomes interdependent and you can no longer change anything. Clojure's advantage is simply that it presented a chance to start over and get things right from the beginning.
- wonderzombie 14y ago
  Right, yes: what ships with the language shapes the way the language is used, and has wider impacts beyond what you could theoretically or even practically do with it. A dumb example would be a Option/Maybe type in Java. You could write a good approximation. But none of the standard libraries would use it, let alone any user supplied libs. Lisps are different in some very important ways, but since this is in part a meatspace phenomenon, it's still a challenge. Somebody went so far as to call it The Lisp Curse[0]. Anyway, syntax is a matter of taste, though I think people focus too much on it one way or the other— people don't like s-expressions b/c parens, people don't like Clojure b/c brackets/braces/whatever. So while I agree that Clojure syntax isn't a huge game-changer, it can and does improve the quality of life for some people, myself included. Built-in literals are a big deal. And there is a lot to be said for being able to use these as primitives on day 1 of learning Clojure, esp. as your first Lisp. [0]: http://www.winestockwebdesign.com/Essays/Lisp_Curse.html http://www.winestockwebdesign.com/Essays/Lisp_Curse.html.

chongli 14y ago

>So, in my opinion, there is absolutely nothing special in this syntactic constructions, moreover, it is not that difficult to implement them using closures and macroses. In arc.arc you could see how strings and tables were implemented. You're right, there is nothing special about what Clojure does; everything could be implemented in Scheme just fine. The real advantage comes from the fact that these things are there "out of the box" so that libraries are written to use them. There is a lot of inertia when it comes to libraries in a language. In some sense, you only get one chance to get it "right" before everything becomes interdependent and you can no longer change anything. Clojure's advantage is simply that it presented a chance to start over and get things right from the beginning.

wonderzombie 14y ago
Right, yes: what ships with the language shapes the way the language is used, and has wider impacts beyond what you could theoretically or even practically do with it. A dumb example would be a Option/Maybe type in Java. You could write a good approximation. But none of the standard libraries would use it, let alone any user supplied libs. Lisps are different in some very important ways, but since this is in part a meatspace phenomenon, it's still a challenge. Somebody went so far as to call it The Lisp Curse[0]. Anyway, syntax is a matter of taste, though I think people focus too much on it one way or the other— people don't like s-expressions b/c parens, people don't like Clojure b/c brackets/braces/whatever. So while I agree that Clojure syntax isn't a huge game-changer, it can and does improve the quality of life for some people, myself included. Built-in literals are a big deal. And there is a lot to be said for being able to use these as primitives on day 1 of learning Clojure, esp. as your first Lisp. [0]: http://www.winestockwebdesign.com/Essays/Lisp_Curse.html http://www.winestockwebdesign.com/Essays/Lisp_Curse.html.