The original hungarian notation uses intention or kind in its naming convention and is sometimes called apps hungarian as it became popular in the microsoft. For those who dont know, hungarian notation is when you name your variables based on their typescope, such as int nbobspaycheck 35. Thus, the c on c prefix should be flagged as an allowed prefix. Depending on the page, window, control, or class, the event names for a page can be, initialized, prerender, rendering, postrender, and exited.
What is hungarian notation in coding standards and why we are. It was developed and published in 1955 by harold kuhn, who gave the name hungarian method because the algorithm was largely based on the earlier works of two hungarian mathematicians. For example, p means pointer, hence, ptextbuf is a pointer to a buffer called textbuf. It was useful in the type less languages like bcpl, because bcpl has no data types, we can identify the variable type by looking at its prefix. Hungarian notation in programming, the use of standard prefixes in naming variables. Sohnee, well the point, that i was trying to make above, the oo naming convention is that everything is logically grouped together using alphasorted lists, so it is just as easy to find as hungarian notation, and doesnt have the pit falls that i have outlined below, because everything is grouped together by their purpose in life instead of their type. Hungarian notation is mainly confined to microsoft windows programming environments, such as microsoft c. In hungarian notation, these extended types are described by the variables prefix.
My personal opinion is that the best hungarian notation is no hungarian notation. Apps hungarian notation in apps hungarian notation, the prefix represents the logical data type, which gives an indication of the objects purpose. C that has many of global variables orand lowerapi that deals with precise data types and sizes e. It was originally devised by charles simonyi, a hungarian, who was a senior programmer at microsoft for many years. What is the benefit of not using hungarian notation.
If you search the web for hungarian notation, you will find a lot of opinions about whether hungarian notation is good or bad. The conventions suggest, among other things, that programmers choose prefixes that are suggestive of the. Each identifier would have two parts to it, a type and a qualifier. Compilers for languages providing typechecking ensure the usage of a variable is consistent with its type automatically. Hungarian notation is an identifier naming convention in computer programming, in which the. The idea of hungarian notation and similar schemes is to reflect the type, scope or other attribute of a variable in its name. Hungarian notation was invented in 1972 by charles simonyi, a microsoft programmer. Hungarian notation prescribes adding a disambiguating mixedcase phrase to the end of the name. Hungarian notation is a convention for naming and differentiating between data objects. The original idea of hungarian notation was to encode information about the variables purpose, which is known as apps hungarian. Over time, this focus changed to encoding information about the variables type andor scope, which is known as systems hungarian.
In general, hungarian notation names a variable with a lowercase prefix to identify the class or usage of the variable. I have wanted to like hungarian notation naming conventions, but never found their value to outweigh costs, such as keeping variable names in sync with their types. I know i havent before, but i came across it 2 days ago and have been comfortably using it since then. The leszynski naming convention or lnc is a variant of hungarian notation popularized by consultant stan leszynski specifically for use with microsoft access development. For instance, an unsafe unsanitized string might have the prefix us, and a variable used for counting might be. The notations inventor, charles simonyi, was hungarian, hence its name. Simonyis colleagues read the variables he named according to his new convention, they discovered the names were not in english. Why i prefer to use hungarian notation tom mcfarlin. Windows api uses the hungarian notation which was intruduced by charles simonyi at microsoft and xerox parc. Yes, it is possible to have more than one prefix for example, you may have a pointer to an array of database records. Hungarian notation online reference techsciencenews.
However, once started, they quickly and quietly turn to deceiving the reader by falsely presenting some ridiculous type encoding technique as hungarian notation. I used to use hungarian notation early in my career, but abandoned it after i read several books and papers about research on coding styles. Although the naming convention is nowadays often used within the microsoft access community, and is the standard in visual basic programming, it is not widely used elsewhere. It is invented by charles simonyi a xerox parc programmer. The benefit of not using hungarian notation is basically only avoidance of its disadvantages.
The hungarian notation is redundant when typechecking is done by the compiler. Yet another author that doesnt know the difference between apps hungarian and systems hungarian. Part 2 most java programs could use better variable names. Variable names, table fields, and other database objects should be in hungarian notation for readability. Many sources advises against this notation and nowadays many ides can provide a variable type by just hovering the mouse over it. Information and translations of hungarian notation in the most comprehensive dictionary definitions resource on the web. Inevitably, the type of a variable will need to change, but you wont want to rename it, so the prefix will be wrong, making the whole idea of hungarian notation pointless because you cant trust it.
C programming standards and guidelines, internal document 81093. I dont even use hungarian notation when i write c code. It was originally proposed by charles simonyi, a programmer at xerox parc in the early 1980s. Seek out and use hungarian warts that have meaning in languages other than your current. When im looking at a string, in order to get the code right, i need to know, everywhere i see that string, whether its safe or unsafe. Bcpl is short for before c programming language and is an ancient designed in 1966, typeless language where everything is a word. In c the length of a variable name is unlimited although the first 31. Give events names with a concept of before, current, and after, using the present and past tenses.
Indicator data type example c character curcustomer. Hungarian notation is an identifier naming convention in computer programming, in which the name of a variable or function indicates its intention or kind, and in some dialects its type. As an example of the two, consider prefixing variables with l for length, a for area and v for volume. Used correctly, it includes the data type in the name of the variable, so you can use it correctly in your code, e. They include variable prefix notations that give to variable names a suggestion of the type of the variable. Standard coding guidelines grid protection alliance. To configure the list of allowed prefixes, bring up the stylecop settings for a project, and navigate to. Hungarian notation in microcontroller code codeproject. Because bcpl has no data types other than the machine word, nothing in the language itself helps a programmer remember variables types. This demagogic technique is called straw man argument.
Windows coding conventions win32 apps microsoft docs. In that situation, hungarian notation can help with nakedeye. Oct 14, 2019 hungarian notation uncountable computing, programming a naming convention in which the name of a variable indicates its data type and intended use by including abbreviations as prefixes. For what its worth, i as a hungarian can tell you, that hungarian as a language does not read or sound at all like hungarian notation. Camel case refers to using uppercase for the inital letters of each word within an identifier name, j. May 11, 2005 this business of making wrong code look wrong depends on getting the right things close together in one place on the screen. Both terms are used in the context of programming languages, and they both relate to the naming of identifiers variable names, type names etc. Hungarian notation found its first major use with the bcpl programming language. Every company and programmer seems to have their own flavor of hungarian. Where can i find a cheat sheet for hungarian notation. If you run stylecop 5, it will complain about variables starting with is, stylecop 4. Prefixes vary from platform and company, so you can never be sure if, for example, di is double integer, digital input, dumb intern, or what. General style and coding standards for software projects. These have become a common coding practice in win32 programming.
Systems hungarian is the bad kind, where names are prefixed with their compiler types, e. One notation that we all use is spaces to make it easier to read code. The complete type of a variable is given by the combination of the prefixes and base type. This list will assist in standardizing the structure, coding style and logic of an application. Some programmers have an intense dislike for hungarian notation. Coding style conventions are used in this sample series to aid clarity and consistency. Because microstations resource compilers have grown from c style programming, structs that are shared with the microstations dialog manager must conform to c rules. This one has only four main code examples, but rather extensive ones. For example, i means an index, cb means a size in bytes count of bytes, and rw and col mean row and column numbers.
Hungarian notation wikimili, the best wikipedia reader. With such notation, the following expression makes sense. It allows a programmer to quickly see what type of data is being used in a section of code. In its original form, hungarian notation gives semantic information about a variable, telling you the intended use. Hungarian notation is clearly goodbad sutters mill.
Most books in this genre have many short code examples. Oct 17, 2016 it evolved when there were fewer ides editing tools, and when compilers werent as supportive. Contribute to robojacketshungarian development by creating an account on github. According to this convention the variable name begins with a lower case letter or letters that denotes the data type of the variable. Definition of hungarian notation in the dictionary. What is the difference between camelcase and hungarian.
The following page is meant as an introduction to one such standard naming convention that is widely adopted. The original hungarian notation uses intention or kind in its naming convention and is sometimes called apps hungarian as it became popular in the microsoft apps division in the development of word, excel and other apps. Hungarian notation is the tactical nuclear weapon of source code obfuscation. Hungarian notation in c programming language hungarian notation is a variablenaming convention so called in the honor of the legendary microsoft programmer charles simonyi. The original, good, definition is the apps hungarian notation, but most people use the systems hungarian notation. Also the variable names should be self descriptive. Intro to mfc 5 oo software design and construction hungarian notation variable prefix naming convention to more easily identify type and scope, wo having to refer back to the definition, most mfc programmers employ hungarian charles simonyi notation. In programming, hungarian notation is a set of conventions for naming data objects in which a programmer adds a meaningful prefix of one or several characters to the objects name to identify what type of object it is. Coding style conventions win32 apps microsoft docs. The hungarian notation has primarily been popularised by microsoft and their corresponding usage of it in their apis, articles, code samples and reference. Prefix data type ar array b boolean cchar cclass dw dword, double word or unsigned long fn. Systems hungarian notation and apps hungarian notation. Stylecop 5 only shows the explicit excpetions for hungarian notation. What is hungarian notation in coding standards and why we.
Except for the szar prefix zero terminated character array, iirc, which has a meaning in hungarian. System hungarian notation apps hungarian notation if you are designing in procedural language e. Hungarian notation was designed to be languageindependent, and found its first major use with the bcpl programming language. Some examples for procedure names name description initsy takes an sy as its argument and initializes it. For example, a variable named c onexecute c will appear to stylecop to be using hungarian notation, when in reality it is not. Charles simonyi, a hungarianamerican computer software executive, is credited with creating the hungarian notation. Because b c you use the notation np which means no problem. Hungarian notation was invented for a language bcpl that didnt have a type system, and was later used widely in a language c that had a fairly limited number of native types. It is especially efficient, because the disambiguation always tacks onto the end of nameswhich is easy to add and remove in the editor if you ever run up against a collision. So now ill walk you through a little example, and then ill show you a general rule you can use for inventing these coderobustness conventions, and in the end it will lead to a defense of a certain type of hungarian notation, probably not the type that makes people carsick, though, and a criticism of exceptions in certain circumstances. When i am taking notes in school i use my own notation so i can keep up. I was just thinking to myself, how many of nowadays programmers actually use hungarian notation. If youve ever looked at the mangled names of variables that compiler generates to stick in object files youll see some hungarian notation thatll drill your eyes out of their sockets. The notation was originally meant to denote the intended usage of a variable rather than its type but its usually used for type information, particularly for form controls e.
Even the examples that come with the java sdk from sun could be improved, since many programmers are going to study them and learn from them. Its funny how often we forget the name of the type of casing when writing variable names. There is no such thing as standard hn, so the point here is to create a consistent notation system. This notation uses a prefix to denote the variable type. It is a naming convention in which variable type and scope are specified as a prefix to the variable name. Charles simonyi is credited with first discussing hungarian notation. The hungarian notation is a languageindependent programming naming convention. Hungarian notation is an identifier naming convention in computer programming. A more common form of hungarian notation uses prefixes to give type informationfor example, dw for dword and w for word. Notations that incorporate type information in variable names have mixed utility in typeunsafe languages notably c, are possible but have no benefits only drawbacks in objectoriented languages, and are impossible in generic programming. Hungarian notation technical university of denmark. Hungarian notation is used in naming variables and data types. How to write unmaintainable code department of software. For instance, an unsafe unsanitized string might have the prefix us, and a variable used for counting might be prefixed with n.
For example pipewt is a bad choice for a variable, as the use of that variable is not clear looking at its name. Hungarian notation is a naming convention in computer programming, in which the name of a variable indicates its type or intended use. The following tips will help you corrupt the original intent of hungarian notation. The hungarian notation is a languageindependent programming naming convention wherein the name of an object designates its type and usage. The original apps hungarian style used by the office iirc added prefixes based on logical information about the data, rather than about the types e. Hungarian notation is a naming convention in computer programming that indicates either the type of object or the way it should be used. The hungarian method is a combinatorial optimization algorithm that solves the assignment problem in polynomial time and which anticipated later primaldual methods. This is a list of visual basic control and object prefixes provided as a reference for consistent use of hungarian notation. When hungarian notation is used, a programmer adds an indicator prefix to each object name to easily and readily identify its type.
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