Question: How Can I do statically numerical calculation?

Hi, I have defined a function like b1_Func := (t) -> b[1]+t; The value of b[1] is being updated somewhere in the code, but I do not want this change in b[1] influences the initial definition of my function. i.e. I want to define it as initial value of b[1]. How can I do that? Moreover, in general, how can I define variables which must be calculated just once without any update? e.g. b:=x+1 and x is changing, but I don't want this change to influence the last calculated value of b Thank you,
Please Wait...