Replace(String,F,T,From,Cnt) 
 New P,I
 Set P=1
 For I=1:1:$G(From) Set P=$F(String,F,P) Quit:'P
 Quit:'P
 Set:'$G(Cnt) Cnt=9999
 For  Quit:'Cnt  Set P=$F(String,F,P) Quit:'P  Do
 .Set $E(String,P-$L(F),P-1)=T
 .Set P=P-$L(F)+$L(T)
 .Set Cnt=Cnt-1
 Quit String