whack v.
According to arch-hacker James Gosling (designer of
NeWS, GOSMACS and Java), to "...modify a program with no
idea whatsoever how it works." (See whacker.) It is actually
possible to do this in nontrivial circumstances if the change is
small and well-defined and you are very good at glarking
things from context. As a trivial example, it is relatively easy
to change all stderr
writes to stdout
writes in a
piece of C filter code which remains otherwise mysterious.