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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-6
votes
4answers
160 views

Java constructor: I can't understand [on hold]

I am learning Java and I have a problem understanding the concept of constructor for the field variables. What is the problem with the following code. It shows "null" as an output. public class ...
-2
votes
1answer
58 views

What is the technical term for anything that can obtain a reference? [on hold]

In programming, you have properties, methods, variables, constants, classes, interfaces, enums, attributes, etc. Properties and methods are considered class members, but not necessarily everything ...
4
votes
8answers
628 views

One-use variables - has any language ever had them?

A principle that I follow is that, when an identifier is established, it should be a signal to the reader that the value referred to is indeed an abstraction which will be used more than once. That ...
2
votes
2answers
211 views

Avoid This Pointer

PROBLEM: this points to different instances at different stages of execution (as it should). But it is not always obvious which instance is that. On the other hand we could minimize the use of this, ...
1
vote
2answers
94 views

What is the use case for shadowing variables?

One of the things the coffeescript programming language is criticized for is its treatment of variable declarations and scope (example). The answers to this question (and the blog I linked to above) ...
-3
votes
3answers
89 views

Best way to handle variables used in a for loop? [duplicate]

From previous experience, I had always thought that, if you are going to use variables inside of a for loop, it was much better to declare them outside of the loop vs. inside the loop itself. I ...
-4
votes
2answers
63 views

Rationale for modern languages implement changeable global variables [closed]

Common sense seems to be that usage of global variables is bad, in particular if they are used as real variables (i.e. changing state; e.g. Why is Global State so Evil?). How does it come then, that ...
1
vote
3answers
8k views

Why am I seeing more boolean naming conventions where “is” is used as the first word in the variable (eg, IsUserAdmin vs UserIsAdmin)? [closed]

I think everyone will agree that the following boolean variable/property names are standard: UserIsAdmin OrdersAreClosed The important thing to note about boolean expressions is that they are ...
37
votes
9answers
3k views

Using compound statements (“{” … “}” blocks) to enforce variable locality [duplicate]

Introduction Many "C-like" programming languages use compound statements (code blocks specified with "{" and "}") to define a variables scope. Here is a simple example. for (int i = 0; i < 100; ...
38
votes
12answers
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
1answer
139 views

What is internal state and is there a difference between state and internal state

Ok, this question has been asked before, but it's still not clear to me. What exactly is internal state? So far state is clear to me: Functions contain behavior, variables have state, values don't. ...
11
votes
3answers
4k views

Handling extremely large numbers in a language which can't?

I'm trying to think about how I would go about doing calculations on extremely large numbers (to infinitum - intergers no floats) if the language construct is incapable of handling numbers larger than ...
1
vote
2answers
185 views

Should I declare variables at the top of the function for reasons other than the scope rules?

In JavaScript, one should declare all variables at the beginning of the function to mitigate the risk of mistakes related to the fact that the scope of variables is a function. The following code ...
-3
votes
1answer
135 views

grouping variables into a system in C? [closed]

Within C, say I have a number of variables, floats, integers etc, is there a way that I can group them all into one object, lets call it a system, and then create N copies of such an object. Further, ...
1
vote
4answers
112 views

What is the Pythonic convention for working with an object similar to an existing variable? [closed]

I often have an object, like a list or a dictionary, that I want a variation on. I might want a list with each element changed somehow (perhaps with a list comprehension, or could be a complicated ...
0
votes
1answer
49 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. ...
2
votes
1answer
119 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 ...
4
votes
5answers
359 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 ...
3
votes
2answers
539 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
128 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 ...
1
vote
1answer
90 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
340 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
1k 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
114 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
13k 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 ...
2
votes
3answers
672 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
154 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
91 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
333 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
639 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
16k 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
323 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
2k 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 ...
0
votes
1answer
1k 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
571 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
244 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
106 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 ...
18
votes
4answers
3k 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
5k 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
4k 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
564 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) { ...
28
votes
6answers
17k views

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

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 ...
22
votes
2answers
3k 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
283 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
290 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
281 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
2k 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
94 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 ...