added "no_assms" option to Refute, and include structured proof assumptions by default;
will do the same for Quickcheck unless there are objections
header {* Main HOL *}
theory Main
imports Plain Nitpick Predicate_Compile
begin
text {*
Classical Higher-order Logic -- only ``Main'', excluding real and
complex numbers etc.
*}
text {* See further \cite{Nipkow-et-al:2002:tutorial} *}
end