csh questions and bugs

[Michael Cohen]

In doing some csh programming I seem to notice two features which
it would be nice to modify.

Query,  when csh is doing a search using its history mechanism and the
search is unsuccessful, is there any way to turn off the error return.
What I want to be done is the original argument to be passed along and
and the procedure continued.  This is useful for using the csh substitute
mechanism along with the alias facility.  I also noted that

      set foo=`            \newline
`

fails, i.e. backquote mechanism expects to necessarily find matching
quote on same line.

Finally set foo=`sed '-e s/\./\\./g -e s/\*/\\(\.\*\\)/g'` fails but
set sedvar='-e s/./\\./g -e s/\*/\\(\.\*\\)/g',
set foo=`sed $sedvar` succeeds.  I'm don't understand the reason for
the differing behavior.