If I want to flip some bits, I was wondering which way is better. Should I flip them using XOR 0xffffffff or by using ~? I'm afraid that there will be some cases where I might need to pad bits ont...

I'm trying to negate the max-device-width media query (the reason for this is I don't won't both (max-device-width: X) and (min-device-width: X) to fire if the device has precisely that width). Unf...

How do I write an if statement in Lua that negates (inverts/flips) a Boolean variable used as the condition? For example, in Java, one can write: boolean a; a = false; if (!a) { //do something } ...

Say I have the following theory: a(X) :- \+ b(X). b(X) :- \+ c(X). c(a). It simply says true, which is of course correct, a(X) is true because there is no b(X) (with negation as finite failure...

In my application I use several profiles to make certain beans eligible for autowiring. What I'm missing is the possibility to make a bean eligible for autowiring when a certain profile is NOT acti...

I've had a hard time searching for clear answers on negation in Prolog, so I apologize if this is an obvious question: I'm trying to write a simple code that will logically say that "X and Y love...

I've been working with PHP for quite a while now, but this was always a mystery to me, the correct use of the exclamation mark (negative sign) in front of variables. What does !$var indicate? Is v...

How would I use a negative form of Python's isinstance()? Normally negation would work something like x != 1 if x not in y if not a I just haven't seen an example with isinstance(), so I'd l...

I want to select spans that are not the descendants of a specific class, let's call it "no". Here's my CSS: div:not(.no) span{background-color:#00f;} Here's the HTML <div> <span>y...

I came across an article which mentioned that the result of !0 is compiler dependent. The result can be either 1 or FF or FFFF and so on. As for C99 standard 6.5.3.3 Unary arithmetic operators, ...

How can I write the following rule in PROLOG: if P then not Q I understand that you can easily write if P then Q the predicates like q(X) :- p(X), but how can you negate the q/1 predicate? I don't...

I'm trying to create a directory if the path doesn't exist, but the ! (not) operator doesn't work. I'm not sure how to negate in Python... What's the correct way to do this? if (!os.path.exists("/...

I am trying to solve a simple query in Prolog that uses negation but I can't crack it. The query is "Find the categories that have never been sold". The knowledge base is as follows: category(sta...

Strange question, but someone showed me this, I was wondering can you use the not ! operator for int in C++? (its strange to me). #include <iostream> using namespace std; int main() { int ...

I know how to build filters and Q objects in django, but I don't know how to negate the operators that the API provides, for example for the contains operator I would like something like notcontain...

In the code below, from a blog post by Alias, I noticed the use of the double exclamation mark !!. I was wondering what it meant and where I could go in the future to find explanations for Perl syn...