The appropriate separation of concerns is a fundamental engineering principle. A concern, for software developers, is that which must be represented by code in a program; by extension, separation of concerns is the ability to represent a single concern in a single appropriate programming language construct. Advanced separation of concerns...
Successful software systems evolve over their lifetimes through the cumulative changes made by software maintainers. As software evolves, the problems resulting from software change worsen, exacerbated by increased system size and complexity, lack of program understanding, amount of effort required to make changes, and number of personnel involved. Experience shows...