implementation of timeout in the testbench

Dear All,

normally I tend to write this:

variable t: time;

t := now;

wait until rising_edge(MemReadQxM) for 150 ns;

xassert (now-t < 150 ns, "BUS TIMEOUT");

is there any 'nicer'/more sophisticated way how to write such assertion? can I avoid the delta t calculation?

thanks

david