December 27th, 2009

eyes black and white

Boston Lisp Meeting: Monday 2010-01-25 Ryan Culpepper on PLT Scheme Macros

A Boston Lisp Meeting will take place on Monday, January 25th 2010 at 1800 at NEU WVH 366. Ryan Culpepper will speak about PLT Scheme Macros.

Additionally, we will have two 5-minute Lightning Talks, each followed by 2-minute Q&A. Speakers to be announced.

Note that lacking a sponsor at this point, no buffet will be offered after the meeting.

1 Ryan Culpepper on PLT Scheme Macros

I will talk about writing macros in PLT Scheme, using the tools I've developed. The first tool is the macro stepper, which shows the macro expansion of programs as a series of rewriting steps. The macro stepper is adapted specifically to the challenges of writing macros in a hygienic macro system using a base language that is itself composed of layers of macros. I'll demonstrate how to use the macro stepper and talk about its implementation. The second tool I'll demonstrate is a specification system for Scheme syntax that makes macros robust and concise.

I am a graduate student in the PLT group at Northeastern University working on making macros more powerful and easier to use. I'm interested in exploring new ways of expressing programs and methods of implementing and supporting program expression.

2 Lightning Talks

At every meeting, before the main talk, there are two slots for strictly timed 5-minute "Lightning Talks" followed by 2 minutes for questions and answers.

The slots for next meeting are still open. Step up and come talk about your pet project! Contact me at fare at

3 Time and Location

The Lisp Meeting will take place on Monday, January 25th 2010 at 1800 (6pm) at NEU WVH 366.

Note that it's the same location as in our previous December 2009 meeting, and a different location from earlier meetings.

This is at Northeastern University, in the Computer Science building WVH (West Village H, see this picture) when you arrive from the T on Huntington Avenue near to Parker St (Green E line, stop at Northeastern Station, or possibly Museum of Fine Arts; you can also walk from Ruggles on the Orange line). As the number indicates, the room is on the third floor.

Northeastern maps and direction:

Many thanks go to Eli Barzilay for arranging for the room, and to Northeastern University for welcoming us.

4 No Dinner

We haven't been able to renew sponsorship from our usual partners at this point, and we won't have the usual buffet after this meeting.

5 More about the Meeting

The previous Boston Lisp Meeting on Monday, December 14th 2009 had about 20 participants. Sam Tobin-Hochstadt spoke about Typed Scheme.

We're always looking for more speakers. The call for speakers and all the other details are at: Volunteers to give Lightning Talks are also sought.

For more information, see our web site For posts related to the Boston Lisp meetings in general, follow this link: or subscribe to our RSS feed:

Please forward this information to people you think would be interested. Please accept my apologies for your receiving this message multiple times. My apologies if this announce gets posted to a list where it shouldn't, or fails to get posted to a list where it should. Feedback welcome by private email reply to fare at