for (SCM s = newas; gh_pair_p (s); s = gh_cdr (s))
{
SCM what = gh_caar (s);
int alter = gh_scm2int (gh_cdar (s));
int pos = alteration_pos (what, alter, c0p);
for (SCM s = newas; gh_pair_p (s); s = gh_cdr (s))
{
SCM what = gh_caar (s);
int alter = gh_scm2int (gh_cdar (s));
int pos = alteration_pos (what, alter, c0p);