Questions tagged [operators]
Operators are symbols that occur in nearly all programming and coding languages, used for performing calculations, comparisons, and assignments of data. Use this tag for any questions relating to operators, in any language, including things such as syntax, behaviour and use.
operators
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What is the '-->' operator in C/C++?
After reading Hidden Features and Dark Corners of C++/STL on comp.lang.c++.moderated, I was completely surprised that the following snippet compiled and worked in both Visual Studio 2008 and G++ 4.4. ...
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answers
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views
Does Python have a ternary conditional operator?
Is there a ternary conditional operator in Python?
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Which equals operator (== vs ===) should be used in JavaScript comparisons?
I'm using JSLint to go through JavaScript, and it's returning many suggestions to replace == (two equals signs) with === (three equals signs) when doing things like comparing idSele_UNVEHtype.value....
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Reference Guide: What does this symbol mean in PHP? (PHP Syntax)
What is this?
This is a collection of questions that come up now and then about syntax in PHP. This is also a Community Wiki, so everyone is invited to participate in maintaining this list.
This ...
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What is the !! (not not) operator in JavaScript?
I saw this code:
this.vertical = vertical !== undefined ? !!vertical : this.vertical;
It seems to be using !! as an operator, which I don't recognize. What does it do?
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Why don't Java's +=, -=, *=, /= compound assignment operators require casting?
Until today, I thought that for example:
i += j;
Was just a shortcut for:
i = i + j;
But if we try this:
int i = 5;
long j = 8;
Then i = i + j; will not compile but i += j; will compile fine.
...
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What does the ??!??! operator do in C?
I saw a line of C that looked like this:
!ErrorHasOccured() ??!??! HandleError();
It compiled correctly and seems to run ok. It seems like it's checking if an error has occurred, and if it has, it ...
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What are the basic rules and idioms for operator overloading?
Note: This question and the original answers are from 2010 and partially outdated. Most of it is still good and helpful, but the original text no longer covers everything there is to know about C++ ...
- 223k
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What is ':-!!' in C?
I bumped into this strange macro code in /usr/include/linux/kernel.h:
/* Force a compilation error if condition is true, but also produce a
result (of value 0 and type size_t), so the expression ...
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answers
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Is there a "null coalescing" operator in JavaScript?
Is there a null coalescing operator in Javascript?
For example, in C#, I can do this:
String someString = null;
var whatIWant = someString ?? "Cookies!";
The best approximation I can figure out for ...
- 57.6k
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What are bitwise shift (bit-shift) operators and how do they work?
I've been attempting to learn C in my spare time, and other languages (C#, Java, etc.) have the same concept (and often the same operators)...
At a core level, what does bit-shifting (<<, >&...
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11
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Behaviour of increment and decrement operators in Python
How do I use pre-increment/decrement operators (++, --), just like in C++?
Why does ++count run, but not change the value of the variable?
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JavaScript plus sign in front of function expression
I’ve been looking for information about immediately invoked functions, and somewhere I stumbled on this notation:
+function(){console.log("Something.")}()
Can someone explain to me what the + sign ...
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What is the use of the @ symbol in PHP?
I have seen uses of @ in front of certain functions, like the following:
$fileHandle = @fopen($fileName, $writeAttributes);
What is the use of this symbol?
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"is" operator behaves unexpectedly with integers
Why does the following behave unexpectedly in Python?
>>> a = 256
>>> b = 256
>>> a is b
True # This is an expected result
>>> a = 257
>>> b = ...
- 979k