[Uim] Question about schemas + bonus hangeul question =P

[David Oftedal]

I've been looking through the .scm files for a few minutes, and some of 
the lines are quite straightforward:

     ((("a"). ())("あ"."ア"))
     ((("i"). ())("い"."イ"))

However, there are a lot of lines whose function isn't very obvious. Is 
there a howto out there that describes the format of these schemas?

Also, I was wondering about the hangul2 schema. It has about 2542 
entries. However, I've read that the actual combination of hangeul that 
can be written is somewhere near 17000. Do you just drop those, or is 
there a mechanism that combines those 2542 into 17000 combinations?

-Dave Oftedal