\dhead{fun}{cerror-with-location @<floc> @<continue-string>
@<datum> \&rest @<arguments>}
\dhead{fun}{cerror*-with-location @<floc> @<datum> \&rest @<arguments>}
\dhead{fun}{cerror-with-location @<floc> @<continue-string>
@<datum> \&rest @<arguments>}
\dhead{fun}{cerror*-with-location @<floc> @<datum> \&rest @<arguments>}