guideline

Use overwriting for conditional assignment when measured performance indicates.

   -- Using "if .. else"
   if Condition then
      Var := One_Value;
   else
      Var := Other_Value;
   end if;
   -- Using overwriting
   Var := Other_Value;
   if Condition then
      Var := One_Value;
   end if;

rationale

Determine the impact of styles of assigning alternative values. The examples illustrate two common methods of doing this; for many systems, the performance difference is significant.