https://principles-wiki.net/ 2026-04-22T13:48:16+00:00 https://principles-wiki.net/ https://principles-wiki.net/_media/logo.png text/html 2013-05-19T20:09:22+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:abstractions_live_longer_than_details?rev=1368994162&do=diff Abstractions Live Longer Than Details [see GP] text/html 2021-10-18T19:20:45+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:add_more_classes?rev=1634584845&do=diff Add More Classes Variants and Alternative Names Context * Object-Oriented Design Principle Statement " “When things get too complex, add more classes.”" Description Complexity can often be reduced by adding further classes that better separate concerns. Rationale text/html 2021-10-18T19:21:27+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:constantine_s_law?rev=1634584887&do=diff Constantine's Law Variants and Alternative Names * Low Coupling, High Cohesion Context * Object-Oriented Design * API Design * Architecture Principle Statement " “A structure is stable if cohesion is strong and coupling is low.”" Description This principle is a combination of the two principles text/html 2013-05-19T20:09:21+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:crash_early?rev=1368994161&do=diff Crash Early [see FF] text/html 2014-04-26T11:52:14+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:curly_s_law?rev=1398513134&do=diff Curly's Law [see SRP] text/html 2021-10-18T19:23:43+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:dependency_inversion_principle?rev=1634585023&do=diff Dependency Inversion Principle (DIP) Variants and Alternative Names Context * Object-Oriented Design * API Design Principle Statement Depend on abstractions. Description A simplified description of DIP is that a variable declaration should always have the (static) type of an abstract class or text/html 2013-05-19T20:09:16+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:direct_mapping?rev=1368994156&do=diff Direct Mapping [see MP] text/html 2021-10-18T19:40:56+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:do_it_myself?rev=1634586056&do=diff Do It Myself [see IE] text/html 2014-04-26T11:52:36+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:do_one_thing?rev=1398513156&do=diff Do One Thing [see SRP] text/html 2025-08-31T12:09:54+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:don_t_repeat_yourself?rev=1756642194&do=diff Don't Repeat Yourself (DRY) Variants and Alternative Names * Single Point of Truth (SPOT) * Single Source of Truth (SSOT) Context * Object-Oriented Design * Implementation Principle Statement " “Every piece of knowledge must have a single, unambiguous, authoritative representation within a system. text/html 2021-10-18T19:28:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:don_t_talk_to_strangers?rev=1634585306&do=diff Don't Talk To Strangers [see LoD] text/html 2026-02-12T10:28:09+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:easy_to_use_and_hard_to_misuse?rev=1770892089&do=diff Why healthcare reform? Individuals claimed that the cost this would definately be less and would give better services. Can estimated how the healthcare bill will cost trillions. When you've got look in the overall picture you can see that involved with not financially sustainable. You will have to pay hundreds of dollars before it actually starts to pay for your healthcare. Government is inefficient in everything it manages. Private Enterprise does a much better job. text/html 2026-02-12T11:22:09+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:encapsulate_the_concept_that_varies?rev=1770895329&do=diff Now that healthcare reform is almost reality, you're ready identify details and nonwinners. Overall, I feel the nation can be a loser within the one. Big government programs usually result in massive corruption, mind-boggling inefficiencies, and shameful amounts of waste. And after this 宮崎市 整体院 we're it will our healthcare to arrange? Yikes! Drilling down into the specifics we find the real winners and losers. It is interesting that the uninsured are these! text/html 2013-05-19T20:09:20+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:explicit_is_better_than_implicit?rev=1368994160&do=diff Explicit Is Better Than Implicit (EIBTI) [see RoE] text/html 2021-10-18T19:33:23+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:fail_fast?rev=1634585603&do=diff Fail Fast (FF) Variants and Alternative Names * Rule of Repair * Crash Early Context * Implementation * API Design Principle Statement A design is better when fails fast, i.e. as soon as an unrepairable erroneous condition is encountered. Description Check for erroneous conditions like wrong parameter values, unmet preconditions, violated invariants, etc. In case of methods this means that it checks for errors and reports them for example by means of throwing an exception. text/html 2013-08-02T14:31:41+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:fallacies_of_distributed_computing?rev=1375453901&do=diff Fallacies of Distributed Computing Variants and Alternative Names Context * Architecture Principle Statement " Essentially everyone, when they first build a distributed application, makes the following eight assumptions. All prove to be false in the long run and all cause big trouble and painful learning experiences. text/html 2026-02-12T05:00:54+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:gall_s_law?rev=1770872454&do=diff To try out and go as well as adjust spending beyond a 10-year mark would be so devastating to federal government and the economy that it is a non-starter. Because of this, I'm going to us a 10-year type of adjusted engaging in. The debate over national healthcare is going to be discussed during the country in town hall meetings from coast to coast this month of August, as congress is in summer break. It made me regarding a personal comparison I have between our healthcare system and could can s… text/html 2013-05-19T20:09:25+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:general_principle_of_robustness?rev=1368994165&do=diff General Principle Of Robustness [see Postel's Law] text/html 2021-10-20T19:20:29+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:generalization_principle?rev=1634757629&do=diff Generalization Principle (GP) Variants and Alternative Names * Build Generality into Software * Abstractions Live Longer than Details * Rule of Power (RoP) Context * Object-Oriented Design * API Design * Architecture * User Interface Design * Implementation Principle Statement A generalized solution, that solves not only one but many problems, is better than a specific one. text/html 2021-10-18T19:36:42+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:high_cohesion?rev=1634585802&do=diff High Cohesion (HC) Variants and Alternative Names Context * Object-Oriented Design * API Design * Architecture Principle Statement Cohesion in a module should be high. Description The cohesion of a module is a measure for how well the internal parts of a module (e.g. the methods and attributes of a class) belong together. Having a high cohesion means, that a module should only comprise responsibilities which belong together. text/html 2021-10-18T19:25:12+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:information_expert?rev=1634585112&do=diff Information Expert [see TdA/IE] text/html 2021-10-18T19:56:28+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:information_hiding_encapsulation?rev=1634586988&do=diff Information Hiding/Encapsulation (IH/E) Variants and Alternative Names * Parnas' Law Context * Object-Oriented Design * API Design * Architecture Principle Statement Modules should be encapsulated. Description Information hiding and encapsulation are sometimes seen as one and sometimes as two separate but related notions text/html 2021-10-18T19:55:36+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:interface_segregation_principle?rev=1634586936&do=diff Interface Segregation Principle Variants and Alternative Names Context * Principle Statement Don't expose methods to your client, methods that they don't use. Description Rationale Exposing functionality that the client class does not need at most a security risk and at the very least noise for the client class. You don't want your class's clients to recompile if some method they don't use changed. text/html 2021-10-18T19:53:11+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:invariant_avoidance_principle?rev=1634586791&do=diff Invariant Avoidance Principle (IAP) Variants and Alternative Names Context * Object-Oriented Design Principle Statement Avoid Invariants and Preconditions. Description Methods typically have preconditions. Something that has to be true prior to invoking the method so it can work properly. Typical cases are parameters that may not be text/html 2026-02-20T23:07:56+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:keep_it_simple_stupid?rev=1771628876&do=diff Working with a roofing contractor Joliet team can help catch damage early and plan repairs before water spreads.(Image: https://burst.shopifycdn.com/photos/red-rooftops-and-curved-streets-of-lisbon-portugal.jpg?width=746&format=pjpg&exif=0&iptc=0) If you notice water stains, damp insulation, or recurring drips after storms, leak detection and repair should be scheduled sooner rather than later. Targeted repairs can help extend roof life when the overall system is still in good shape. When a roof… text/html 2021-10-18T19:52:10+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:law_of_demeter?rev=1634586730&do=diff Law of Demeter (LoD) Variants and Alternative Names * Principle of Least Knowledge * Don't Talk to Strangers Context * Object-Oriented Design * Implementation Principle Statement “A method of an object should invoke only the methods of the following kinds of objects: text/html 2021-10-18T19:51:22+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:law_of_leaky_abstractions?rev=1634586682&do=diff Law Of Leaky Abstractions (LLA) Variants and Alternative Names Context * Architecture * API Design Principle Statement " All non-trivial abstractions, to some degree, are leaky." A solution is bad if * the leakiness of abstractions is ignored (bad usage of an abstraction) or text/html 2021-10-18T19:50:50+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:liskov_substitution_principle?rev=1634586650&do=diff Liskov Substitution Principle (LSP) Variants and Alternative Names Context * Object-Oriented Design * API Design Principle Statement " “Subtypes must be substitutable for their base types.”" Description Object-oriented programming languages permit the derivation of subtypes from base types, and subtype polymorphism allows the passing of an object of a subtype where ever an object of the supertype is specified. Suppose text/html 2026-03-04T18:14:52+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:low_coupling?rev=1772648092&do=diff The lawyers may because the biggest those who win. This bill is a dream come true for all ambulance chasers. There aren't limits indicates. The millions they get for malpractice suits will keep their butts in plush offices and fancy cars forever. I have a doctor friend that pays over $100,000 a year in malpractice insurance on your own. Keep that in mind the next occasion you complain about my doctor bill. Looking in the air of a text/html 2021-10-18T19:48:52+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:miller_s_law?rev=1634586532&do=diff Miller's Law Variants and Alternative Names Context * User Interface Design Principle Statement Any list should not contain more than 7±2 items. Description Lists such as items in the main menu of a program or bullets on a presentation slide should be limited to 7±2 items. text/html 2013-05-19T20:09:24+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:minimize_coupling_between_modules?rev=1368994164&do=diff Minimize Coupling Between Modules [see LC] text/html 2021-10-18T19:47:52+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:model_principle?rev=1634586472&do=diff Model Principle (MP) Variants and Alternative Names * Direct Mapping * Low Representational Gap (LRG) Context * Object-Oriented Design * API Design * Architecture * User Interface Design Principle Statement The object structure of the software should model and mirror those concepts and actions of the real world, that the software supports. text/html 2021-10-20T19:26:19+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:more_is_more_complex?rev=1634757979&do=diff More Is More Complex (MIMC) Variants and Alternative Names * Less is more Context * Object-Oriented Design * API Design * Architecture * User Interface Design * Implementation * Documentation Principle Statement More is more complex. Description Having more lines of code, methods, classes, packages, executables, libraries etc. always means also to have more complexity (which is bad). This means that given the complexity of the problem is fixed, a suitable compromise for t… text/html 2021-10-20T19:18:46+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:murphy_s_law?rev=1634757526&do=diff Murphy's Law (ML) Variants and Alternative Names * Design for Errors Context * Object-Oriented Design * API Design * User Interface Design * Implementation Principle Statement Whatever can go wrong, will go wrong. So a solution is better the less possibilities there are for something to go wrong. text/html 2021-10-18T19:44:38+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:one_responsibility_rule?rev=1634586278&do=diff One Responsibility Rule [see SRP] text/html 2022-03-02T22:55:39+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:open-closed_principle?rev=1646261739&do=diff Open-Closed Principle (OCP) Variants and Alternative Names Context * Object-Oriented Design * API Design Principle Statement Modules should be open for extension but closed for modification. Description Rationale Strategies Caveats Beware that wrong application of OCP may lead to the anti-pattern text/html 2019-07-05T10:10:27+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:pit_of_success?rev=1562321427&do=diff Pit Of Success [See EUHM] text/html 2021-10-18T19:43:00+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:postel_s_law?rev=1634586180&do=diff Postel's Law Variants and Alternative Names * General Principle of Robustness (not to be confused with Eric S. Raymond's Rule of Robustness) Context * Object-Oriented Design * API Design Principle Statement " “Be conservative in what you do, be liberal in what you accept from others. text/html 2013-05-19T20:09:23+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:principle_of_least_astonishment?rev=1368994163&do=diff Principle Of Least Astonishment (PLA) [see PLS] text/html 2013-05-19T20:09:22+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:principle_of_least_knowledge?rev=1368994162&do=diff Principle Of Least Knowledge [see LoD] text/html 2021-10-18T20:16:13+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:principle_of_least_privilege?rev=1634588173&do=diff Principle Of Least Privilege Variants and Alternative Names * principle of minimal privilege * principle of least authority Context * Security Principle Statement Every program and every privileged user of the system should operate using the least amount of privilege necessary to complete the job. text/html 2021-10-18T20:15:28+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:principle_of_least_surprise?rev=1634588128&do=diff Principle Of Least Surprise (PLS) Variants and Alternative Names * Principle of Least Astonishment (PLA) * May also be referred to as “rule” or “law” instead of “principle” * Acronyms sometimes include the “o” for “of”: PoLA, PoLS text/html 2021-10-18T20:13:23+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:principle_of_separate_understandability?rev=1634588003&do=diff Principle Of Separate Understandability (PSU) Variants and Alternative Names Context * Object-Oriented Design * Implementation Principle Statement Each module shall be understandable on its own---without knowing anything about other modules. Description PSU means that: * text/html 2021-10-18T20:06:14+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:rule_of_explicitness?rev=1634587574&do=diff Rule of Explicitness (RoE) Variants and Alternative Names * Explicit Is Better Than Implicit (EIBTI) Context * Object-Oriented Design * API Design * Implementation Principle Statement Explicit is better than implicit. Description Solutions often differ in the level of explicitness. A feature can be implemented explicitly or it can be a side-effect of the implementation of another feature or a more general functionality. The same applies to module communication. A module can inv… text/html 2013-05-19T20:09:17+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:rule_of_least_surprise?rev=1368994157&do=diff Rule Of Least Surprise [see PLS] text/html 2018-06-24T09:03:06+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:rule_of_power?rev=1529830986&do=diff Rule of Power (RoP) [see GP] text/html 2021-10-18T20:04:58+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:rule_of_repair?rev=1634587498&do=diff Rule Of Repair [see FF] text/html 2013-05-19T20:09:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:rule_of_simplicity?rev=1368994158&do=diff Rule of Simplicity [see KISS] text/html 2013-05-19T20:09:21+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:separation_of_concerns?rev=1368994161&do=diff Separation Of Concerns (SoC) [see SRP] text/html 2021-10-18T20:03:31+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:single_level_of_abstraction?rev=1634587411&do=diff Single Level of Abstraction (SLA) Variants and Alternative Names * One Level of Abstraction * Don't Mix Different Levels of Abstractions Context * Implementation * Object-Oriented Design Principle Statement Each method should be written in terms of a single level of abstraction. text/html 2013-05-19T20:09:27+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:single_point_of_truth?rev=1368994167&do=diff Single Point Of Truth (SPOT) [see DRY] text/html 2021-10-18T20:01:35+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:single_responsibility_principle?rev=1634587295&do=diff Single Responsibility Principle (SRP) Variants and Alternative Names * One Responsibility Rule * Separation of Concerns (this originally was a broader term but is mostly used just like SRP) * Curly's Law * Do One Thing Context * Object-Oriented Design * text/html 2013-05-19T20:09:19+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:single_source_of_truth?rev=1368994159&do=diff Single Source Of Truth (SSOT) [see DRY] text/html 2025-12-29T16:23:12+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:start?rev=1767025392&do=diff Principles * Abstractions Live Longer Than Details [see GP] * Add More Classes * Constantine's Law * Crash Early [see FF] * Curly's Law [see SRP] * Dependency Inversion Principle (DIP) * Direct Mapping [see MP] * Do It Myself [see IE] * Do One Thing [see SRP] * Don't Repeat Yourself (DRY) * Don't Talk To Strangers [see LoD] * easy_to_use_and_hard_to_misuse * encapsulate_the_concept_that_varies * Explicit Is Better Than Implicit (EIBTI) [see RoE] * Fail Fast (FF) * Fallacies of… text/html 2021-10-18T19:42:15+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:tell_don_t_ask_information_expert?rev=1634586135&do=diff Tell Don't Ask/Information Expert (TdA/IE) Variants and Alternative Names * Information Expert or Expert in * Do It Myself in * Tell, don't Ask in Context * Object-Oriented Design * Implementation Principle Statement * Assign a responsibility to that module which has the largest subset of the required information. text/html 2025-08-31T12:13:25+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:uniformity_principle?rev=1756642405&do=diff Uniformity Principle (UP) Variants and Alternative Names Context * Object-Oriented Design * API Design * Architecture * User Interface Design * Implementation * Documentation Principle Statement Solve similar problems in the same way. Description Software design comprises many similar tasks. There are plenty of design decisions that are similar to ones taken before. UP tells that a design is good when similar design problems are solved the same way. UP can be applied to a la… text/html 2026-04-20T22:07:46+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:you_ain_t_gonna_need_it?rev=1776722866&do=diff That counterbalance is on the button what makes a matter utilitarian crossways many types of cognitive content si It gives the article a unclouded focus, keeps the terminology readable, and makes the political platform itself feeling to a greater extent perceivable to newly visitors. In the end, the family kit and caboodle because it gives multitude a clearer way of life toward what they already get it on they delight. For anyone written material astir Frompo.com, secrecy tip is a fresh issue be… text/html 2021-10-18T19:58:34+00:00 Anonymous (anonymous@undisclosed.example.com) https://principles-wiki.net/principles:zero_one_infinity?rev=1634587114&do=diff Zero One Infinity (ZOI) Variants and Alternative Names Context * Object-Oriented Design Principle Statement " Allow none of foo, one of foo, or any number of foo." Description Rationale Strategies Caveats See section . Origin Evidence Relations to Other Principles