Java: What does ~ mean
The Tilde (~) performs a bitwise complement of a numerical value in Java. See: Bitwise complement (~): inverts ones and zeroes in a number
operators
What does the ^ (caret) symbol do in JavaScript?
The ^ operator is the bitwise XOR operator. To square a value, use Math.pow: var altura2 = Math.pow($(‘#ddl_altura’).attr(“value”)/100, 2);
What does the ^ (XOR) operator do? [duplicate]
XOR is a binary operation, it stands for “exclusive or”, that is to say the resulting bit evaluates to one if only exactly one of the bits is set. This is its function table: a | b | a ^ b –|—|—— 0 | 0 | 0 0 | 1 | 1 1 | 0 … Read more
What are the pointer-to-member operators ->* and .* in C++?
I hope this example will clear things for you //we have a class struct X { void f() {} void g() {} }; typedef void (X::*pointer)(); //ok, let’s take a pointer and assign f to it. pointer somePointer = &X::f; //now I want to call somePointer. But for that, I need an object X x; … Read more
Not equal to != and !== in PHP
== and != do not take into account the data type of the variables you compare. So these would all return true: ‘0’ == 0 false == 0 NULL == false === and !== do take into account the data type. That means comparing a string to a boolean will never be true because they’re … Read more
Overriding “+=” in Python? (__iadd__() method)
Yes, override the __iadd__ method. Example: def __iadd__(self, other): self.number += other.number return self
What’s the difference between ++$i and $i++ in PHP?
++$i is pre-increment whilst $i++ post-increment. pre-increment: increment variable i first and then de-reference. post-increment: de-reference and then increment i “Take advantage of the fact that PHP allows you to post-increment ($i++) and pre-increment (++$i). The meaning is the same as long as you are not writing anything like $j = $i++, however pre-incrementing is … Read more
Is there no XOR operator for booleans in golang?
There is not. Go does not provide a logical exclusive-OR operator (i.e. XOR over booleans) and the bitwise XOR operator applies only to integers. However, an exclusive-OR can be rewritten in terms of other logical operators. When re-evaluation of the expressions (X and Y) is ignored, X xor Y -> (X || Y) && !(X … Read more
How can I calculate divide and modulo for integers in C#?
Here’s an answer from the MSDN documentation. When you divide two integers, the result is always an integer. For example, the result of 7 / 3 is 2. To determine the remainder of 7 / 3, use the remainder operator (%). int a = 5; int b = 3; int div = a / b; … Read more
What is the difference between “::” “.” and “->” in c++ [duplicate]
1.-> for accessing object member variables and methods via pointer to object Foo *foo = new Foo(); foo->member_var = 10; foo->member_func(); 2.. for accessing object member variables and methods via object instance Foo foo; foo.member_var = 10; foo.member_func(); 3.:: for accessing static variables and methods of a class/struct or namespace. It can also be used … Read more