Here is a list of all documented files with brief descriptions:

containers.h
error.h
expressions.h
fda.h
floating_array.h
fnv.h
FRC.h
interpolate.h
kbsm.h
logger.h
machines.h
parser.h
random.h
replacer.h
tests.h
tr.h
tstrings.h
unicode.h
vnum.h