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jolux
Please tell me RET is a backronym for return like you'd hit when you've finished a line in a REPL ;)
lispm
Imagine if they detect that Lisp and Smalltalk have Inspectors for data... -> more blog posts about the wonders of 'REPL', Clojure and Functional Programming.

> clojure.core defines the vars print-length and print-level

I wonder where all this is coming from? ;-)

Lisp programmers practice interactive 'bottom up programming' for decades now.

See for example Erik Sandewall's article 'Programming in an Interactive Environment: the "Lisp" Experience' from 1978:

https://www.ida.liu.se/ext/caisor/archive/1978/001/caisor-19...

j-pb
Clojure is a lisp.
davexunit
I think what lispm is getting at is that there a large number of Clojure programmers that do not realize that Clojure's features and the workflows it enables have been around for decades.
j-pb
Fair enough, I guess the article is aimed mostly at newbies to clojure though, which mostly come from a non-lisp background.
lispm
That style of interactive exploratory programming is supported by a gazillion of languages and implementations. There is nothing Clojure specific about it.

From the early Lisp to most other forms of Lisp-derived languages (like Logo, Dylan, ...), over APL, Mathematica, up to Apple's Swift...

j-pb
Neither is the article nor I arguing that in any way. It is a case study of developing a clojure program in the repl, done to inspire newcomers, not a scientific article claiming clojure invented the repl.
lispm
It explicitly mentions clojure, functional programming and a repl to enable this.

None of that is necessary. One can nicely use Smalltalk (recent version: Pharo), its object-oriented programming and its interactive IDE for that.

j-pb
Just because it mentions it doesn't means it claims it's necessary.

The author states

" If you're new to Clojure, or functional programming, or languages that have a REPL, I hope this encourages you to crack open a REPL and start to think about your own story. It's a means to whatever end you have in mind. "

and even points to a super general google search.

https://www.google.de/search?client=safari&rls=en&q=repl+dri...

Did you actually read the thing, or just open it close it and decide to hat it because it not CL?

lispm
> Did you actually read the thing, or just open it close it and decide to hat it because it not CL?

The author could benefit from some of the better REPLs of Common Lisp - which for example nicely integrate various tools (inspectors, debuggers, error handling, object-oriented programming, ...) to better support interactive/exploratory programming.

lispm
Can it run Lisp code?
j-pb
Which lisp?
junke
The one that was painfully standardized to avoid this kind of question?

"The Lisp family of languages" vs "Lisp" is an old discussion: see http://lisp-univ-etc.blogspot.fr/2013/01/common-lisp-is-just... for a summary.

j-pb
Ah so scheme then. Fair enough, scheme is probably the most worthy of the title. It's both true to McCarthys mathmatical spirit, and he himself stated that Steele is probably the closest thing to a benevolent dictator in the lisp world.
lispm
Steele hasn't edited the Scheme standard since two or three decades.

Ever wondered why Scheme is called Scheme and not LexicalLisp?

It's a new language, with it's own dialects, standards, libraries, implementations, communities, ...

Lately Steele worked on languages like Java and Fortress. Nothing with Lisp...

j-pb
Yeah why would he. We don't revise lambda calculus every year.
lispm
Yet, Scheme has seen many standard revisions. Without Steele editing it.

The Scheme standard has been edited by others, not Steele. Since three decades. From R2RS in 1985 up to R7RS in 2013.

lispm
McCarthy's Lisp.

http://www.softwarepreservation.org/projects/LISP/lisp15_fam...

Its core lives in every Lisp.

j-pb
Fair enough, but then no lisp in use today is lisp.
lispm
Its core lives in Lisp dialects like Emacs Lisp just fine.

Try GNU Emacs and the REPL:

    M-x ielm

    *** Welcome to IELM ***  Type (describe-mode) for help.
    ELISP> (append '(this is a Lisp) '(REPL))
    (this is a Lisp REPL)

    ELISP> (cons 'This (append '(is a) (list 'Lisp 'REPL)))
    (This is a Lisp REPL)
This code is from McCarthy's Lisp 1.5 Programmer's manual, from 1962, running in Common Lisp:

    CL-USER 6 >  (defun my-length (l)
                   (prog (u v)
                     (setq v 0)
                     (setq u l)
                     a
                     (cond ((null u) (return v)))
                     (setq u (cdr u))
                     (setq v (+ v 1))
                     (go a)))
    MY-LENGTH

    CL-USER 7 > (my-length '(1 2 3 4 5))
    5
That's why it's called a 'Lisp' -> it runs Lisp code.
davexunit
Yet another person discovering the beauty of the REPL. On my own time, I write all of my software in Guile Scheme using Emacs + Geiser[0] as a development environment and it's wonderful. I wish my work environment could be half as nice as that.

[0] http://geiser.nongnu.org/geiser_1.html#Introduction

magicbuzz
Swift has a REPL. On an OS X command line, simply type 'swift'.