I'm curious what you mean by this, why it's needed or would be a good thing, etc. As a multi-paradigm language, I'm not seeing why CL should have a particular paradigm "all the way down".
It's good because it offers the opportunity to simplify and rationalize the type system and associated protocols without losing features.
In the early 1990s I worked on an experimental Newton OS written in Dylan. At that time, Dylan was still called "Ralph," and it was basically an implementation of Scheme in which all datatypes were CLOS classes. It was "CLOS all the way down."
Ralph offered substantially the same affordances and conveniences as Common Lisp, but with a simpler and more coherent set of APIs. Ralph was easier to learn and remember, and easier to extend.
To illustrate why, consider finite maps. The idea of a finite map is a convenient abstraction with a well-defined API. Common Lisp offers a couple of convenient ways to represent finite maps, and it's easy to build new representations of them, but there's no generic API for finite maps. Instead, each representation has its own distinct API that has nothing particularly to do with anything else.
By contrast, Ralph had a single well-defined API that worked with any representation of finite maps, whether built-in or user defined.
The upshot is a library of datatypes that is just as rich as Common Lisp's, but with a simpler and more coherent set of APIs, and an easy standard way to extend them with user-defined types that also support the same APIs.
There are signs in the Common Lisp standard that people were already thinking in that direction when the standard was defined. See the sequence functions, for example. Ralph, designed by Common Lisp and Smalltalk implementors, carried that thinking to its logical conclusion, and the result was something like a tidier Common Lisp.
Twenty-eight years later, Ralph is still my favorite of all the languages I've used for serious work. Its development system, Leibniz, remains my favorite development system. My favorite current tools are Common Lisp systems, but that's because I can't have Ralph and Leibniz anymore.
My favorite current tools are Common Lisp systems, but that's because I can't have Ralph and Leibniz anymore.
You said below that you don't find modern day Dylan to be as valuable. I don't know much about Dylan, either the pre-1992 version or the newer version(s), but I'm curious if you would elaborate on why the older Dylan was so much superior to modern Dylan in your view?
Uniformity, which is a really good thing. Surely you could say
(class-of 3) or (class-of nil) or (class-of '(1 2 3))
but technically these values are not objects, like it is in, say, Scala, which is a real-world example of how good it is to have a uniform language (everything is an expression, every value is an instance of a class, and therefore everything is uniformly high-order, uniformly typed (unlike Java with distinctions of so-called primitive types) etc, etc.
Uniformity through imposing one paradigm on everything isn't attractive at all to me, especially for a paradigm I have no interest in using and avoid when I practically can.
Every value in CL is an instance of class. Some of those classes are built-in classes, which are restricted for performance reason. You do not inherit from Int in Scala either, since it is marked as "final", as far as I know.
mikelevins|7 years ago
In the early 1990s I worked on an experimental Newton OS written in Dylan. At that time, Dylan was still called "Ralph," and it was basically an implementation of Scheme in which all datatypes were CLOS classes. It was "CLOS all the way down."
Ralph offered substantially the same affordances and conveniences as Common Lisp, but with a simpler and more coherent set of APIs. Ralph was easier to learn and remember, and easier to extend.
To illustrate why, consider finite maps. The idea of a finite map is a convenient abstraction with a well-defined API. Common Lisp offers a couple of convenient ways to represent finite maps, and it's easy to build new representations of them, but there's no generic API for finite maps. Instead, each representation has its own distinct API that has nothing particularly to do with anything else.
By contrast, Ralph had a single well-defined API that worked with any representation of finite maps, whether built-in or user defined.
The upshot is a library of datatypes that is just as rich as Common Lisp's, but with a simpler and more coherent set of APIs, and an easy standard way to extend them with user-defined types that also support the same APIs.
There are signs in the Common Lisp standard that people were already thinking in that direction when the standard was defined. See the sequence functions, for example. Ralph, designed by Common Lisp and Smalltalk implementors, carried that thinking to its logical conclusion, and the result was something like a tidier Common Lisp.
Twenty-eight years later, Ralph is still my favorite of all the languages I've used for serious work. Its development system, Leibniz, remains my favorite development system. My favorite current tools are Common Lisp systems, but that's because I can't have Ralph and Leibniz anymore.
unknown|7 years ago
[deleted]
mindcrime|7 years ago
You said below that you don't find modern day Dylan to be as valuable. I don't know much about Dylan, either the pre-1992 version or the newer version(s), but I'm curious if you would elaborate on why the older Dylan was so much superior to modern Dylan in your view?
Immortalin|7 years ago
throwaway487548|7 years ago
dwc|7 years ago
junke|7 years ago
e12e|7 years ago