fix inconsistent uses of tok
test character reading
tests for comments
fix comment reader
characters and comments now tested in the reader
add a coerce function to the typefn_t
call arc_string2num to see if we can read a number
coerce defined as null
arc_list_append
coerce slot in tfn
coerce slot in tfn
coerce slot in tfn
coerce slot in tfn
slot for coerce
slot for coerce
slot for coerce
slot for coerce
arithmetic functions header
add arith.h to noinst headers
arithmetic defs