separation of concerns

aesthetics  →
being  →
complexity  →
database  →
enterprise  →
ethics  →
fiction  →
history  →
internet  →
knowledge  →
language  →
licensing  →
linux  →
logic  →
method  →
news  →
perception  →
philosophy  →
policy  →
purpose  →
religion  →
science  →
sociology  →
software  →
truth  →
unix  →
wiki  →
essay  →
feed  →
help  →
system  →
wiki  →
critical  →
discussion  →
forked  →
imported  →
original  →
separation of concerns
[ temporary import ]
please note:
- the content below is remote from Wikipedia
- it has been imported raw for GetWiki
In computer science, separation of concerns (SoC) is a design principle for separating a computer program into distinct sections, such that each section addresses a separate concern. A concern is a set of information that affects the code of a computer program. A concern can be as general as the details of the hardware the code is being optimized for, or as specific as the name of a class to instantiate. A program that embodies SoC well is called a modularBOOK, Laplante, Phillip, What Every Engineer Should Know About Software Engineering, 2007, CRC Press, 0849372283,weblink program. Modularity, and hence separation of concerns, is achieved by encapsulating information inside a section of code that has a well-defined interface. Encapsulation is a means of information hiding.BOOK, Mitchell, Dr. R. J., Managing Complexity in Software Engineering, 1990, IEE, 0863411711, 5,weblink Layered designs in information systems are another embodiment of separation of concerns (e.g., presentation layer, business logic layer, data access layer, persistence layer).BOOK, Microsoft Application Architecture Guide, 2009, Microsoft Press, 0-7356-2710-X,weblink The value of separation of concerns is simplifying development and maintenance of computer programs. When concerns are well-separated, individual sections can be reused, as well as developed and updated independently. Of special value is the ability to later improve or modify one section of code without having to know the details of other sections, and without having to make corresponding changes to those sections.


The mechanisms for modular or object-oriented programming that are provided by a programming language are mechanisms that allow developers to provide SoC.PAPER, Painter, Robert Richard, Software Plans: Multi-Dimensional Fine-Grained Separation of Concerns,, Penn State, For example, object-oriented programming languages such as C#, C++, Delphi, and Java can separate concerns into objects, and architectural design patterns like MVC or MVP can separate content from presentation and the data-processing (model) from content.Service-oriented design can separate concerns into services. Procedural programming languages such as C and Pascal can separate concerns into procedures or functions. Aspect-oriented programming languages can separate concerns into aspects and objects.Separation of concerns is an important design principle in many other areas as well, such as urban planning, architecture and information design.BOOK, Garofalo, Raffaele, Building Enterprise Applications with Windows Presentation Foundation and the Model View ViewModel Pattern, 2011, Microsoft Press, 0735650926, 18,weblink The goal is to more effectively understand, design, and manage complex interdependent systems, so that functions can be reused, optimized independently of other functions, and insulated from the potential failure of other functions.Common examples include separating a space into rooms, so that activity in one room does not affect people in other rooms, and keeping the stove on one circuit and the lights on another, so that overload by the stove does not turn the lights off. The example with rooms shows encapsulation, where information inside one room, such as how messy it is, is not available to the other rooms, except through the interface, which is the door. The example with circuits demonstrates that activity inside one module, which is a circuit with consumers of electricity attached, does not affect activity in a different module, so each module is not concerned with what happens in the other.


, Dijkstra, Edsger W, Edsger W. Dijkstra, On the role of scientific thought,weblink
, Selected writings on Computing: A Personal Perspective, 1982, 60â€“66, Springer-Verlag, New York, NY, USA, 0-387-90652-5,
, Reade, Chris, Chris Reade, Elements of Functional Programming
, Addison-Wesley Longman, 1989, Boston, MA, USA, 0-201-12915-9, that describes separation of concerns:
Reade continues to say,


Internet protocol stack


HTML, CSS, JavaScript


Subject-oriented programming


Aspect-oriented programming

Aspect-oriented programming allows cross-cutting concerns to be addressed as primary concerns. For example, most programs require some form of security and logging. Security and logging are often secondary concerns, whereas the primary concern is often on accomplishing business goals. However, when designing a program, its security must be built into the design from the beginning instead of being treated as a secondary concern. Applying security afterwards often results in an insufficient security model that leaves too many gaps for future attacks. This may be solved with aspect-oriented programming. For example, an aspect may be written to enforce that calls to a certain API are always logged, or that errors are always logged when an exception is thrown, regardless of whether the program's procedural code handles the exception or propagates it.WEB
, PDF, Building Secure Applications
, Jess Nielsen
, June 2006
, 2012-02-08

Software build automation


Levels of analysis in artificial intelligence


Normalized Systems


SoC via partial classes

Separation of concerns can be implemented and enforced via partial classes.WEB
, PDF, Hyper/Net: MDSoC Support for .NET
, Tiago Dias
, October 2006
, 2007-09-25
, DSOA 2006

SoC via partial classes in Ruby

class Bear
def hunt
# TODO: return some food
class Bear
def eat( food )

class Bear
attr_accessor :hunger
def monitor_hunger
if @hunger > 50 then
@hunger -= self.hunt )

See also




External links

{{Edsger Dijkstra}}

- content above as imported from Wikipedia
- "separation of concerns" does not exist on GetWiki (yet)
- time: 2:34am EST - Mon, Dec 17 2018
[ this remote article is provided by Wikipedia ]
LATEST EDITS [ see all ]
M.R.M. Parrott