I am creating an ontology for urban systems. For instance if we have the variable that indicate the size of the population I would name it (using the so called camel notation) sizeOfPopulation. The length of the street as lengthOfStreet. Is there a specific or standardized way of doing it?
There is no correct answer to this question because it's extremely subjective.
Programming Style, Coding Conventions and Naming Conventions.
You are probably familiar with: Tabs versus Spaces?
TL;DR: Choose a style with your team or for youself, and be consistent. Look at strictly managed open source code for ideas, eg: Qt, ChibiOS, Linux.
Related
I find that many databases are named with a prefix 'smt_' in industry, for example, 'smt_customer_profile', what dose 'smt' mean? Is there any special meaning in this prefix?
I have asked my supervisor about this question, getting the answer that the reason behind this naming is very geek style, which really invokes my curiosity! So I tried to google it, some interpretations are like:
satisfiability modulo theories (SMT)
Simultaneous multithreading
Small Mini-Tower
all seemingly not the right answer...
So does anybody know about this, many thanks!!!
Haven't seen this in the industry myself, but the best guess would be Subscription Management Tool, this is what I found SMT in relation to databases:
https://www.suse.com/documentation/smt11/book_yep/data/book_yep.html
It's part of SUSE Linux operating system
What the actual meaning of smt is could be anything. This falls into a class of naming conventions called Hungarian notation -- that is a prefix that defines the "type" or "class" of an object.
Sometimes this was literally the type -- in other cases it might be the equivilant to a modern module (before object oriented programming).
In any case it is very old fashioned and has been replaced with name spaces or schemas for most things.
I am facing certain C/AL tasks those days and as I am used to code in c#, C/AL seems a bit "different" in several aspects.
In particular I am wondering, why it is recommed to use variable names starting with uppercase letters.
From my point of view it would be a benefit in terms of readability to use camelcase notation for variables.
Is there any reason, why it is recommed that way by Microsoft?
I do not think there is a specific reason why the Pascal Case (first letter always uppercase) is used. That being said it is more of a guideline for all developers so that the code is uniform across all products. The general idea is that if you merge code from two different sources (e.g. two different developers) the end result would appear as if the code was from a single source.
Some companies have their own internal rules how code should be formatted. I prefer the use of the naming conventions specified by Microsoft because:
it makes my code consistent with the Navision standard code (objects in the range 1..49999),
it makes my code consistent with my coworkers (our company policy is to use the Microsoft naming conventions).
The MSDN Naming Conventions page states:
"Precise and consistent terminology helps the end user work with the application. Rules for naming and abbreviating objects also help developers to understand the CRONUS International Ltd. demonstration database and develop new features faster."
Pascal Case should be used for general code consistency and overall uniformity but is not necessary or required. I would advise you to consult your company policy on Naming Conventions and follow those or if you are starting fresh to follow the Microsoft naming guidelines.
I hope this doesn't get closed due to being too broad. I know it comes down to personal preference, but there is an origin to all casing conventions and I would like to know where this one came from and a logical explanation as to why people use it.
It's where you go all like var empName;. I call that lower camel, although it's probably technically called something else. Personally, I go like var EmpName. I call that proper camel and I like it.
When I first started programming, I began with the lower camel convention. I didn't know why. I just followed the examples set by all the old guys. Variables and functions (VB) got lower camel while subs and properties got proper camel. Then, after I finally acquired a firm grasp on programming itself, I became comfortable enough to question the tactics of my mentors. It didn't make logical sense to me to use lower camel because it wasn't consistent, especially if you have a variable that consists of one word which ends up being in all lowercase. There is also no validation mechanism in place to make sure you are appropriately using lower vs. upper camel, so I asked why not just use proper camel for everything. It's consistent since all variable names are subject to proper camelization.
Having dug deeper into it, it turns out that this is a very sensitive issue to many programmers when it is brought to question. They usually answer with, "Well, it's just personal preference" or "That's just how I learned it". Upon prodding further, it usually invokes a sort of dogmatic reaction with the person as I attempt to find a logical reason behind their use of lower camel.
So anyone want to shed a little history and logic behind casing of the proper camelatory variety?
It's a combination of two things:
The convention of variables starting with lower case, to differentiate from classes or other entities which use a capital. This is also sometimes used to differentiate based on access level (private/public)
CamelCasing as a way to make multi-word names more readable without spaces (of course this is a preference over underscore, which some people use). I would guess the logic is that CamelCasing is easier/faster for some to type than word_underscores.
Whether or not it gets used is of course up to whomever is setting the coding standards that govern the code being written. Underscores vs CamelCase, lowercasevariables vs Uppercasevariables. CamelCase + lowercasevariable = camelCase
In languages like C# or VB, the standard is to start private things with lowercase and start public/protected things with uppercase. This way, just by looking at the first letter you can tell whether the thing you are messing could be used by other classes and thus any changes need more scrutiny. Also, there are tools to enforce naming conventions like this. The one created/used internally at Microsoft is called StyleCop and is available as a free download.
Historically, well named variables in C (a case-sensitive language) consisted of a single word in lower case. UPPERCASE was reserved for macros.
Then came along C++, where classes are usually CapitalizedAndCamelCased, and variables/functions consisting of several words are camelCased. (Note that C people tend to dislike camelCase, and instead write identifiers_this_way.
From there, it spread.
And, yes, probably other case-sensitive languages have had some influence.
lowerCamelCase I think has become popular because of java and javascript.
In java, it is specifically defined why, that the first word should be a verb with small letters where the remaining words start with a capital letter.
The reason why java chose lowerCamelCase I think depends on what they wanted to solve. Java was launched in 1995 as a language that would make programming easy. C/C++ that was often used was often considered difficult and too technical.
This was something java claimed to solve, more people would be able to program and the same code would work on different hardware. The code was the documentation, you didn't need to comment code, just read and everything would be great.
lowerCamelCase makes it harder to write "technical" code because it removes options to use uppercase and lowercase letters to better describe the code from a technical perspective. Java didn't want to be hard, java was the language to use where everyone could learn to program.
javascript in browsers was created in 10 days by Brendan Eich in 1995. Why javascript selected lowerCamelCase I think is because of java. It has nothing to do with java but it has "java" in its name "javascript".
I see a lot of different styles of variable names used in different kind of languages. Sometimes these names are lowercase and using underscores (i.e. test_var) and other times I see variables like testVar.
Is there a specific reason why programmers use different variable name styles in different languages?
It's really just the convention for that programming language.
For example, most Java programs use camel-casing (testVar) while a lot of C programs use _ to seperate words (test_var).
It's completely the choice of the programmer, but most languages have "standard" naming conventions.
As Wiki says :
Reasons for using a naming convention (as opposed to allowing programmers to choose any character sequence) include the following:
to reduce the effort needed to read and understand source code;1
to enhance source code appearance (for example, by disallowing overly long names or abbreviations).
Also there are code conventions in companies that care about readability of their code.
This simplify the code sharing between programmers and they don't spend time to understand what means variables name "aaa" and "bbb".
There is no real reason. Each language and sometimes even platform can have varying naming conventions.
For instance, in .Net TestVar would be seen if it was a public class variable. In C++, testVar would probably be opted for. In Ruby, test_var, etc. It's just a matter of preference by the community and/or creators.
I urge you to follow language standards. I work on a team that has had many developers working on the code over the years, and very few standards have been followed. The majority of our code is nearly unreadable. I have been working on a standardization project for the last several months. It has been very difficult to enforce and get buy-in. I'm hopeful that people will come around as they start seeing the benefits of easy to read code.
For naming conventions/standards keep this in mind:
Follow team/company standards
Follow language standards
Follow the style that the program is already using
Do whatever you want (Not really - if you don't have standards follow
your language standards/conventions.)
what is the best way to declare variable names.... in uppercase ...? .. lowercase? in which area must be declared in any case ... and what name is appropriate depending on the roll of the standard variable ... there are some variables to declare?...sorry for the question..I'm new to the world of programming ... I hope not bother .... =)
Well here are some links for the coding standards for various languages..
This has standards for variable naming and a lot more.
C# coding standards
C++ coding standards
Java coding standards
And here is generic coding standards article that explains the reasoning behind the coding standards.
Atleast for C and C++ we can use Hungarian notation
If:
the language doesn't dictate it; and
your coding standards don't dictate it,
then just make it as readable as possible. Hordes of developers in the future will sing praises to your name for not inflicting horrible code on them.
My personal favorite is all uppercase and underscores for constants (IQ_LIMIT) and camel case for everything else (getItembyId(), itemCount). But that's personal preference, not something written on stone tablets.
It really depends on the programming language you use, and any coding conventions that are followed by a group.
For example, there is the GNU coding standards for writing C code which covers variable names down to the indentation of lines.
For languages, the Code Conventions for the Java Programming Language lays out some coding conventions for capitalization and naming of variables, packages, classes, methods, etc in the Java programming language.
When in Rome, do as the Romans. Each language usually has its own idioms with respect to these sorts of things.
IMO, knowing the scope of a variable is the most important thing. You should know at a glance how much code can effect a variable and how much code will be effected by your changing it. In this way encapsulation (and your sanity) can be maintained. You won't accidentally change a global variable and mysteriously hose the whole program. Also they should stand out like a sore thumb just begging to be refactored away.
Therefore upper-case the first letter for globals (where "global" is any variable that can be seen by more than one function) and lower-case the first letter for every else. Constants traditionally get all caps.
So in studlyCaps style it would be:
GlobalVariable
localVariable
CONSTANTVARIABLE
And using under scores:
Global_Variable
local_variable
CONSTANT_VARIABLE
Whether you use studlyCaps or under scores depends on your programming language and local style (I prefer under scores for their readability and no confusion about capitalization).
In C#, we use PascalCase for properties and methodnames and camelCase for other members. For constants we use CAPS_WITH_UNDERSCORE. For the html elements hungarian notation is used. (I think these are Microsoft standards.)
A corollary to "When in Rome..." is to do as the previous coder has done. When you are working on another developers code or project, you should match your style to the existing style. While seeing a weird convention is puzzling and hard to deal with at first, it is nothing compared to sorting out a file that switches notation and style every couple of functions.
When working on your own project, or as a single developer you can do what is most comfortable within reason.