Calling ev() during function definition

Dear All,

Imagine I do something like (a more complicated version of) this

load(draw) ;

f(x) := 4*x^5 ;
g(x) := 3*x^4 ;

h(x) := ev(f(x)/g(x)) ;

draw2d(explicit(h(x),x,0,7)) ;

If I've understood correctly, the ev() is called separately for each
specific numerical value of x during the draw2d().  A lot of
CPU time could be saved by instead calling the ev()
once and for all at the time h(x) is defined.  Is this possible,
please?

-- 

Thanks,

Dan