I am updating a series of PRG's to optimize them for speed and to get them ready to convert into classes.

I am finding statement's like:


   replace all cpt_code with h->new_cpt for;
      h->new_cpt<>space(10).and..not.subs(h->new_cpt,1,1)$'QHZ'


My updated version is:


   REPLACE ALL Cpt_Code WITH Cdm.new_cpt;
     FOR NOT EMPTY(Cdm.new_cpt) AND NOT LEFT(Cdm.new_cpt,1) $ "QHZ"



In the first example, you can see where I replaced the '<>space(10)' with 'NOT EMPTY()' and
the 'SUBSTR()' with 'LEFT()'


So my question is, in a program with many of these REPLACE statements, what kind of speed advantages will I see with these changes?