Scheme status

I’ve written here before about my efforts to write a Scheme interpreter from scratch.  The last update was in May, but I’m still working on it.  I’ve made 60 git commits since then.  The major thing I’m trying to do is implement macros, but I’m having a hard time of it.  No matter.  When they’re done, I’ll understand macros thoroughly.

Scheming, part 7. The Reader.

I haven’t ‘blogged about my Scheme interpreter in ages.  Development stopped from January through March, but I’ve been working on it again.  Here are links to the earlier articles.

• Scheming, part 6
• Scheming, part 5
• Announcing kbscheme
• Scheming, part 3
• Scheming, part 2
• Scheming, part 1
• Not another Scheme interpreter!

The biggest new development  is the reader.  Most developers call them parsers, but Lisp people call them readers.  I have written six readers for Scheme now, and I’ve effectively completed a class in advanced parsing theory.  The current reader works very well, and I do not want to write another.

Scheming, part 5

Call/cc works!

That’s the big news.  Lots of little tweaks and cleanup, but call/cc is the big deal.  I’d designed the evaluator to handle call/cc way back when, so it wasn’t a major rewrite.  It was just a matter of figuring out exactly what it had to do.

Announcing kbscheme

I published my scheme interpreter on gitorious.  Now you can follow along.  It needed a name, so I called it kbscheme.  Not a brilliant name but it’ll do.

Here’s the project blurb.

kbscheme

This vanity project is yet another implementation of the Scheme programming language.

Project goals:

• I want to learn Scheme.
• I want to write something in C. I’ve been using higher level languages and my C is rusty.
• I want to write a garbage collector. They’ve always fascinated me, but I’ve never written one.
• I have some research ideas about garbage collection that I want to explore.

Project non-goals:

• a production-quality Scheme interpreter
• full implementation of the language

Check it out, Brandon.

Hint to the git-ignorant (as I was very recently).  Go to the repositories/mainline page and click on the “More info…” links,  Those will show the exact commands needed to copy (clone) the tree onto your local disk.

Actually, I’m still git-ignorant.  Gotta work on that…