[Help-bash] if and [ ] equivalence

[Bill Gradwohl]

If I have a function that can optionally accept parameters, I can write :

   if func ; then
and the equivalent can be said:

   [ func ] &&

If, however, func needs to have a passed parameter, 
   [ func parm ] && 

fails with "unary operator expected"

Is there any way to specify the [ ] method with a passed parameter?

Thank You

-- 
Bill Gradwohl