Variable or scalar is a storage location paired with an associated symbolic name (an identifier), which contains some known or unknown quantity or information referred to as a value.

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2
votes
1answer
81 views

Patterns for sharing context variables between functions

I am looking for ways of passing around a set of contextual variables that are required by functions. As a Python programmer, right now I can see three ways of solving the problem: passing them ...
0
votes
0answers
69 views

Using a PHP loop or MySQL table for arrays values

I have the following results page from the previous form: <?php //Get the form results (which has been converted to an associative array) from the $_POST super global $musicgenres = ...
4
votes
5answers
336 views

What was the reason for the creation of boolean variables?

I found out that some languages like C don't have support for boolean variables and programmers use integers with values of 0 and 1 instead. Is there any specific reason why some languages moved away ...
0
votes
1answer
32 views

Dealing with data containing integer overflow, rollover

I am writing a small matlab function to analyze data from a laser probe. The data to be analyzed is basically: x-data: Position. y-data: Laser (light) intensity. ...
3
votes
2answers
516 views

Giving variables default values vs. treating accessing an undefined variable as an error

Having messed around with several scripting languages and being a bit of a linguist, there seems to be a way to divide dynamically typed languages into two groups: languages that give variables a ...
0
votes
2answers
119 views

The correct way of declaring & instantiating variables ( Javascript ) [duplicate]

I have seen other peoples code and each person has a different way of declaring variables. And I have been told by quite a few people that declaring variables in the Global Scope is wrong. My ...
0
votes
2answers
147 views

Best practice relationship variable naming: Should I use the description of the relationship or variable. Example personId or owner? [closed]

When I'm creating domain models and adding variables to a class. I'm havng to trouble which naming I should use. For example If I have a Person and a Car. When I have: Class Person { var int ...
1
vote
1answer
76 views

Best practices for tracking multiple pieces of data in a program

I have a project in C (don't ask why but it needs to be in C), where I need to track multiple pieces of data and commands for different modules. Some actions that the program will take depend on the ...
2
votes
4answers
304 views

Should I check parameter before using it in methods? [duplicate]

I'm going to build some public PHP packages, Following standards is a priority for me. PHP lets users call methods even if they don't pass required parameters to it. My question. Should I check ...
7
votes
4answers
849 views

Is the use of one-letter variables encouraged? [closed]

Is the use of one-letter variables encouraged in Java? In code snippets or tutorials, you often see them. I cannot imagine using them is encouraged because it makes the code relatively harder to read ...
-2
votes
1answer
88 views

How to name variables without plural in a for-each loop? [closed]

How do you name loop variables when the list item is named after something without a plural? For instance (in python): [x for x in sheep]. x is not a great name, but sheep have/has no plural that ...
7
votes
3answers
10k views

What is meant by Scope of a variable?

I think of the scope of a variable as - "The scope of a particular variable is the range within a program's source code in which that variable is recognized by the compiler". That statement is ...
34
votes
11answers
2k views

Intentional misspellings to avoid reserved words

I often see code that include intentional misspellings of common words that for better or worse have become reserved words: klass or clazz for class: Class clazz = ThisClass.class kount for count in ...
2
votes
3answers
479 views

In C++, should I ever declare a local variable in the corresponding header?

So for example, I create a class with two functions: foo.h class foo { public: foo(); void bar(); void ey(); bool m_memberBool; bool localBool; // ??? Should I put this here? }; ...
2
votes
1answer
111 views

Python beginner question with Assigning Variables

Coming from C# and now getting my hands dirty with Python. From what I understand, Python is strongly typed: http://stackoverflow.com/questions/11328920/is-python-strongly-typed As stated in the ...
-1
votes
1answer
78 views

How to make variables inherent to an object or system [duplicate]

How can one make variables inherent to an object or system? For example, when creating a web browser, each option that is created for the user to have control over (i.e. how a window opens, if ...
2
votes
0answers
130 views

Var assignment in sequence diagram

I am trying to represent the function below (PHP function/Symfony2) as a sequence diagram using UML 2.0 and Visual Paradigm: private function getVeevaHcpSync($request, $action, $case) { ...
1
vote
5answers
472 views

Are there too many parameters in this constructor? [duplicate]

Check this out: public function __construct( \Magento\Framework\Model\Context $context, \Magento\Framework\View\DesignInterface $design, \Magento\Framework\Registry $registry, ...
8
votes
3answers
13k views

Naming conventions for instance, local and parameter variables [closed]

I was discussing with a senior developper coding conventions to apply to our projects (mainly Java/JEE projects). I disagreed with one convention he proposed: Instance variable names should start ...
0
votes
5answers
216 views

Is it bad form to use the same variable name in different scopes?

Say you have some basic code where similar operations will take place in nearby lexical scopes. Take for example some simple pseudo code: variable = "foo" # Do something with variable if (True) { ...
2
votes
3answers
308 views

What is the difference between a variable and a parameter? [closed]

Its a conceptual question. But I would like to use the right term at the right place. That is why I would like to read some other views on this.
8
votes
5answers
2k views

When would dynamic scoping be useful?

With dynamic scoping, a callee can access the variables of its caller. Pseudo C code: void foo() { print(x); } void bar() { int x = 42; foo(); } Since I have never programmed in a ...
-1
votes
1answer
788 views

Python: Faster to use global variable or pass as arguments to a function? [duplicate]

Hey so i was wondering which is the more efficient way, or better practice to do in this situation. 1, def function(): global number number += 2 Or 2, def function(number): return ...
7
votes
2answers
516 views

What is best practice to handle whitespaces when letting the user edit the configuration, the name=value pairs?

For instance, you let the user define the notorious path variable. How do you interpret apppath = C:\Program Files\App? This looks like a programming language adopted practice to ignore the white ...
1
vote
3answers
227 views

Member variables vs. State Varaibels? Are they the same? [closed]

I am learning that member variables are to hold the state of an object? Is it their recommended usage? Are all member variables state variables too? or state variables have specific definition and ...
3
votes
1answer
103 views

Creating variables in methods/functions

In how far do we create variables in our methods or functions? Do we only create one when we're using the result of the variable more then one time like this? function someFunction(SomeClass ...
17
votes
4answers
2k views

Why do we have to mention the data type of the variable in C

Usually in C, we have to tell the computer the type of data in variable declaration. E.g. in the following program, I want to print the sum of two floating point numbers X and Y. ...
5
votes
8answers
4k views

How to abbreviate variable names [closed]

I always struggle in abbreviating variable names. Is there any standard for abbreviating variable names?
13
votes
5answers
3k views

Why is *declaration* of data and functions necessary in C language, when the definition is written at the end of the source code?

Consider the following "C" code: #include<stdio.h> main() { printf("func:%d",Func_i()); } Func_i() { int i=3; return i; } Func_i() is defined at the end of the source code and ...
6
votes
5answers
472 views

Using π, φ, λ etc. as variable names while programming? [duplicate]

This is a function in the d3.v3.js file (the graph library D3.js): function d3_geo_areaRingStart() { var λ00, φ00, λ0, cosφ0, sinφ0; d3_geo_area.point = function(λ, φ) { ...
26
votes
6answers
14k views

Explicitly defining variable data types vs. using the keyword 'var'?

In C#, am I encouraged to use the all-purpose var keyword for every variable declaration? If yes, do I have to mention those special characters for literal values within the variable declaration like ...
21
votes
2answers
2k views

When did the term “snake case” come into use? [closed]

Many people use the term Snake Case to describe variables or other symbols with_the_form_of_underscores. In the past week, I've launched several broad searches. I can't find anything about the origin ...
0
votes
1answer
231 views

Is there a way to prevent variables from changing their type in Python?

It is useful to have the interpreter derive the type of a variable automatically. This on its own is similar to the auto keyword in C++11. However, in Python variables can change their type after ...
2
votes
4answers
220 views

Overwriting and returning the value of the argument used as conditional of an if statement, inside the same if statement

A simplified example: function logTheColor (color){ if(color == "red"){ color = "The color is red " } else if (color == "yellow") { color = "The color is yellow " } else { ...
0
votes
2answers
193 views

Prime symbol in Python variable name

So I'm a terrible person and I want to name a variable in my mathy-python3 code s′ (that's a prime symbol). I was under the impression Unicode literals work as identifiers in Python 3, which is why ...
4
votes
6answers
746 views

Should I store x,y coordinates as an array, a class object, or two variables?

I have a MyObject which has an x and y coordinate. as far as I can see, I can store it in three ways: class MyObject: def __init__(self, x, y): self.x = x self.y = y class ...
0
votes
1answer
72 views

Should instance variables be bound to the instance right in the beginning of the method they are created in?

A common problem for me - and it's not really a problem, but somehow I again and again ask myself, what is the normal way to handle this - is that there is a method and within this method a couple of ...
0
votes
1answer
92 views

Why does this function work even though the vars are different

$inumber1 = 10; $inumber2 = 20; function add($number1, $number2) { echo $number1 + $number2; } add($inumber1, $inumber2); I'm learning PHP coding for the first time and I'm ...
-2
votes
2answers
142 views

php make dollar optional [closed]

Is there any reason the PHP language could not be updated in a future version to make the $ prefix on variable names optional? Reasons that would break existing code? I'm thinking it would still be ...
1
vote
2answers
165 views

Should I sacrifice code succintness to ensure the narrowest variable scope? [duplicate]

In many languages (e.g. both Perl and Java - which are the two languages I work most with) it is possible to narrow the scope of local variables by declaring them within a block. Although it adds ...
0
votes
5answers
371 views

Representation of a question mark in variable names [closed]

I once in my childhood read a SF story in which it was assumed that the capital letter 'P' would be a good representation for a question mark, if you cannot use that character directly, eg. in ...
3
votes
2answers
543 views

Why to declare a String (as final) and then use it?

In a typical spring mvc validator class, while inserting an errorCode value in the Errors object, what difference does it make between using a String (props.somefield.req) like so ...
1
vote
2answers
997 views

What is the underlying mechanism behind va_list and where is it defined?

http://www.cplusplus.com/reference/cstdarg/va_list/ According to the above link, va_list is an argument or parameter used in some macros - va_start, va_arg, va_end. These macros are present in the ...
1
vote
4answers
589 views

Best datatype to store a ternary, or three-state variable

Disclaimer: I know that datatypes are a little bit subjective to which scripting/programming language you are using, I like to write in Python as a matter of preference; though I am happy to hear ...
12
votes
6answers
3k views

Prefer class members or passing arguments between internal methods?

Suppose within the private portion of a class there is a value which is utilized by multiple private methods. Do people prefer having this defined as a member variable for the class or passing it as ...
2
votes
1answer
1k views

Where should variables be declared [duplicate]

Considering I have a for loop in a method of a class. Should the incremented variable be declared as member of the class, or should it be declared in the method it uses it(or even in the for loop, ...
0
votes
3answers
783 views

Isolating unit tests in python

As a 30-year software developer, mostly in OO languages, but a newbie at python, I'm looking to find what is best practise for isolating unit tests in python. Let's say I have the following, ...
13
votes
10answers
3k views

How to write useful Java programs without using mutable variables

I was reading an article about functional programming where the writer states (take 25 (squares-of (integers))) Notice that it has no variables. Indeed, it has nothing more than three ...
2
votes
1answer
59 views

When should I pass setting-like value as class' variable and when as an assoc. array?

Following my other question, is there a general rule of thumb, when we should pass a setting-like value, that controls class' behavior (for example displayed texts) as as class' constant or variable, ...
1
vote
1answer
109 views

When should I pass value as class variable and when as a method argument?

Is there a general rule of thumb, when we should pass a value as as class variable and when as a method argument? Or is it just a choice of the developer? For example -- are there any reasons, why ...