This question already has answers here: Reference — What does this symbol mean in PHP? (23 answers) Closed 6 years ago. PHP 7, which will come out in November this year will introduce the Spaceship (<=>) operator. What is it and how does it work? This question already has an answer in our general reference … Read more
What is the correct name for operator *, as in function(*args)? unpack, unzip, something else? 9 Answers 9
If I am creating my own class in Python, what function should I define so as to allow the use of the in operator, e.g. class MyClass(object): … m = MyClass() if 54 in m: … 3 Answers 3
I’m using maps for the first time and I realized that there are many ways to insert an element. You can use emplace(), operator[] or insert(), plus variants like using value_type or make_pair. While there is a lot of information about all of them and questions about particular cases, I still can’t understand the big … Read more
I was wondering what the = +_ operator means in JavaScript. It looks like it does assignments. Example: hexbin.radius = function(_) { if (!arguments.length) return r; r = +_; dx = r * 2 * Math.sin(Math.PI / 3); dy = r * 1.5; return hexbin; }; 12 Answers 12
While I was trying to learn about C++ operators, I stumbled upon a strange comparison operator on cppreference.com,* in a table that looked like this: “Well, if these are common operators in C++, I better learn them”, I thought. But all my attempts to elucidate this mystery were unsuccessful. Even here, on Stack Overflow I … Read more
I came across the following line hsb.s = max != 0 ? 255 * delta / max : 0; What do the ? and : mean in this context? 8 Answers 8
What does the % in a calculation? I can’t seem to work out what it does. Does it work out a percent of the calculation for example: 4 % 2 is apparently equal to 0. How? 20 Answers 20
Is there any sort of “not in” operator in JavaScript to check if a property does not exist in an object? I couldn’t find anything about this around Google or Stack Overflow. Here’s a small snippet of code I’m working on where I need this kind of functionality: var tutorTimes = {}; $(checked).each(function(idx){ id = … Read more
DataGridView, for example, lets you do this: DataGridView dgv = …; DataGridViewCell cell = dgv[1,5]; but for the life of me I can’t find the documentation on the index/square-bracket operator. What do they call it? Where is it implemented? Can it throw? How can I do the same thing in my own classes? ETA: Thanks … Read more
