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Comment by allover | Hacker News Reader

First I've heard of Red. Does it implement 'readable' [1] or is it a [parallel school of thought] (can't think of right phrase here but you get what I mean)?

Also has anyone tried to create a 'readable' [1] flavour of Clojure yet? If not, why is that, do lispers consider all the parens to really not be a barrier?

[1] http://readable.sourceforge.net/

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Red is basically Rebol rewritten with an important distinction. It comes with a sister language called Red/System that is basically a lightweight static systems language like C, but a lot closer to Red. Therefore, you can run the interpreter or drop down to native code when you need it. The 1.0 release should AOT compile what it can, then JIT, then lastly interpret what you have to. It is hoimoconic like lisp, but not a lisp. There is no install, just a 1 MB interpreter and compiler that can target a lot of architectures. The draw GUI DSL is pretty amazing. There is a Rebol YouTube vid (Red is 98% compatible) where a guy makes a zillion little cool apps with only a few lines of code each.

Link? Searched YouTube but no vids appear to match your description.

https://m.youtube.com/watch?v=lR5Fzv6DP0I

>Does it implement 'readable'

Nope, it has it's own notation which I find very close to the Smalltalk one, for example:

  red>> a: [1]
  == [1]
  red>> pick head append a 1 + 1 2
  == 2
  red>> a
  == [1 2]

So the second expression is good example of how things work, this is how it looks if I put parens (which are unnecessary in this case):

  pick (head (append a (1 + 1))) 2

Here interpreter/compiler knows how many arguments each `word` (you can think `function`) needs, so `append` needs 2 - series and item to append, `head` only one - series, `pick` needs series and index to get element. But what about `+`?

  red>> type? :+
  == op!

Operators are infix things of two arguments and they get priority over function calls, that's why `append` is called with `a` and result of `1 + 1` and not with `a` and `1`.

It looks a bit tricky in the beginning, I understand, but it leads to very compact and easy to read code.

This is brief explanation which should help you to start reading and writing Red/Rebol code :)

Great explanation, thanks!

No, the parens don't constitute a barrier of any kind, really. Reading lisp fluently requires very consistent indentation, though. Then you see where an expr starts and where it ends (with nestings and all) without counting any parens whatsoever.

When writing lisp your editor should help you at least a bit to make things enjoyable. They can help a lot, but doesn't have to help much; I found for myself that if the editor just highlights matching parens, I'll be very effective.

Since discovering paredit-mode, I have found a whole new love for Lisp syntax, and now I won't write Lisp without it.

I have tried a structure editor for Haskell but I found it pretty counterintuitive. I wonder if structure editing just assumes a language with very little syntax.

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