DEFMETHOD vs. DEFUN

[Rik]

jwe,

Why are some built-in functions defined using the macro DEFMETHOD and
others using DEFUN?  I happened to notice in file-io.cc that textscan() is
defined using DEFMETHOD, but it seems like DEFUN should just be used.

If I go to libinterp/corefcn I see a preference for DEFUN, but a fair
number of DEFMETHOD as well.

grep '^DEFUN' *.cc | wc -l
526
grep '^DEFMETHOD' *.cc | wc -l
110

Just curious,
Rik