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Why is “using namespace std;” considered bad practice?
I've been told by others that writing using namespace std; in code is wrong, and that I should use std::cout and std::cin directly instead.
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Safe (bounds-checked) array lookup in Swift, through optional bindings?
...er, I've happened to stumble on a nicer way of implementing this functionality:
Swift 3.2 and newer
extension Collection {
/// Returns the element at the specified index if it is within bounds, otherwise nil.
subscript (safe index: Index) -> Element? {
return indices.contains(i...
Why does PHP 5.2+ disallow abstract static class methods?
...w a load of strict standards warnings from a project that was originally written without strict warnings:
8 Answers
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What are the differences between type() and isinstance()?
... the contents of other (already good!) answers, isinstance caters for inheritance (an instance of a derived class is an instance of a base class, too), while checking for equality of type does not (it demands identity of types and rejects instances of subtypes, AKA subclasses).
Normally, in Python,...
Why aren't python nested functions called closures?
I have seen and used nested functions in Python, and they match the definition of a closure. So why are they called nested functions instead of closures ?
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Calculate a Running Total in SQL Server
...em is that the SQL Server implementation of the Over clause is somewhat limited.
Oracle (and ANSI-SQL) allow you to do things like:
SELECT somedate, somevalue,
SUM(somevalue) OVER(ORDER BY somedate
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)
AS RunningTotal
FROM Table...
Why is try {…} finally {…} good; try {…} catch{} bad?
I have seen people say that it is bad form to use catch with no arguments, especially if that catch doesn't do anything:
20...
Determining complexity for recursive functions (Big O notation)
...a Computer Science Midterm tomorrow and I need help determining the complexity of these recursive functions. I know how to solve simple cases, but I am still trying to learn how to solve these harder cases. These were just a few of the example problems that I could not figure out. Any help would be ...
Can Google Chrome open local links?
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You can't link to file:/// from an HTML document that is not itself a file:/// for security reasons.
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Can I use a :before or :after pseudo-element on an input field?
... am trying to use the :after CSS pseudo-element on an input field, but it does not work. If I use it with a span , it works OK.
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