[epsilon-devel] News about epsilon development

[Luca Saiu]

  Hi Matteo, how are you? Err... happy new year? Some time has passed 
since we met the last time. Sorry for not having written you before now, 
but I had (and am still having) some problems at home, unrelated to 
epsilon and even to me. Now I'm studying Numerical Calculus, and lately 
have had little spare time for epsilon.
  However two weeks ago (last week I have been so busy in the day and 
so tired in the evening that I wasn't even able to *touch* epsilon) I 
completely rewrote epsilonyacc from scratch. Now it's *so* beautiful... :-)
The new epsilonyacc supports canonical LR(1) grammars, so in this 
respect is even more powerful than Bison, but still lacks a frontend. 
This is a funny problem: both epsilonlex and epsilonyacc are compilers, 
so each of them needs a scanner and a parser; how to generate the two 
scanners and the two parsers which we need? Of course, with epsilonlex 
and epsilonyacc! Both epsilonlex and epsilonyacc essentially work and 
generate nice epsilon code, but to give them input I've got to modify 
their sources, by now. So the first versions of the scanners and the 
parsers for the scanner-generator and the parser-generator will be 
generated modifying the sources of the scanner-generator and the 
parser-generator themselves.
  I think it will take me two or three (full-time) days to bootstrap 
epsilonlex and epsilonyacc using themselves; then we'll be able to start 
the meta-interpreter, at last.

  Here's my priority list:

1. make epsilonlex and epsilonyacc bootstrap
2. document exceptions and I/O actions, as you asked me last time
3. finish documenting C libraries, as I promised

  I would be happy if you write some of the graphic primitives we 
talked about, of course if you have some spare time.

  Best regards,

--
Luca Saiu, maintainer of GNU epsilon
http://www.gnu.org/software/epsilon