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henning

OK. Now how about database access (with support for prepared statements), regular expressions, and networking?

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http://paulgraham.com/core.html

Super-duper. I'm not going to use Arc for anything serious until essential libraries are in place.

Darn.

At least you were kind enough to let us know.

Different people have different ideas of serious. To me, exploratory programming is fairly serious, because that's the kind of programming that generates ideas.

Arc is already capable of supporting some subset of applications that are serious in your sense. News.YC is at least moderately serious in that sense.

You said News.YC uses some kind of persistent hash structure for storing everything. This seems to me like Greenspun's Tenth Law except with Berkeley DB instead of Common Lisp; I wouldn't want to write the logic to do what BDB already does much better and faster (I don't want to implement ACID transactions myself if I decide I need them).

news.arc stores all information in flat files as lists.

Well you'll be late to the table for Web 3.0 then... ;-)

clarification: Arc should probably have some kind of database hook at some point, not much point in reinventing that wheel when it works so well for many problems. But that's not the point, as the author has repeatedly pointed out.

Which of those are you planning to contribute?

I'd love to see regular expressions as s-expressions in arc - not pasted on as interpreted strings.

Actually I think I have seen a library for MzScheme that does it this way.

Also curious how this would look

It could look like this: (* (+ "a" (* "b"))) for: "(a+b)" [Perhaps you prefer not to re-use + and * for this.]

Sure, it's somewhat more verbose for this toy examples - but every intermediate expression (and the whole thing) is a Lisp-Object in its own right.

You would not even need macros.

Edit: There is a place for macros here to make things less verbose. Just write a macro that 'compiles': (* (+ a (* b))) into the form above.

For convenience you can offer a function that builds RegExps out of strings in the usual way.

There is a public git repo anyone can push to (the so-called git "wiki", or anarki). It contains regular expressions. You could wrap some DB bindings for mzscheme with relative ease.

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