I'm not doing any coding right now, but I am doing some reading on constraints and "little languages" for layout.

http://hcil2.cs.umd.edu/trs/98-13/dissertation.html

http://www.layx.org/

What I have in mind is creating a small declarative language for user interfaces, with special attention to ncurses- or other textmode programs.

A related project has been to explore a design approach that composes ncurses programs using hierarchical state machines driven by libev's event pump. This is something that got started when I forked Tobias Rapp's mcplay, which is a rewrite in C of the old cplay frontend for mpg123/ogg123. Initially, I only intended to add some UI features like displaying info from the ID3 tags. But mcplay is itself very old now and uses glib-1.2, which I consider an abomination. Last year my forked program began crashing somewhere deep in the bowels of glib and was a royal pain to debug. So I cut the Gordion Knot and began replacing the glib stuff with my own code for linked lists and libev for the event loop. Eventually I grew frustrated with some of the convoluted structure inherited from mcplay and decided to redo the whole thing from scratch. I finished my rewrite earlier this year and have been thinking about ways to do it even better... Still too many global variables and impure functions, for example. Thinking about those flaws is what has me thinking about data structures for layout and "immediate mode user interfaces".

Sorry, I don't yet have my "ncplay" code in an Internet-accessible repository, but will happily email a copy to anyone who would like to take a look at it. Just send me a private message here on nixers.

I'll welcome any pointers to other resources related to declarative approaches to user interface layout.