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#pragma once vs include guards? [duplicate]
... time but #pragma once is very well supported across compilers but not actually part of the standard. The preprocessor may be a little faster with it as it is more simple to understand your exact intent.
#pragma once is less prone to making mistakes and it is less code to type.
To speed up compil...
How to assign the output of a Bash command to a variable? [duplicate]
...
In this specific case, note that bash has a variable called PWD that contains the current directory: $PWD is equivalent to `pwd`. (So do other shells, this is a standard feature.) So you can write your script like this:
#!/bin/bash
until [ "$PWD" = "/" ]; do
echo "$PWD"
ls ...
In C++, what is a virtual base class?
..." diagram is confusing, although it seems to be commonly used. This is actually a diagram showing class inheritance relationships -- not an object layout. The confusing part is that if we do use virtual, then the object layout looks like the diamond; and if we do not use virtual then the object la...
What's the better (cleaner) way to ignore output in PowerShell? [closed]
...ad and > $null has about a 0.3% overhead.
Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different:
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
And no...
Super-simple example of C# observer/observable with delegates
...
The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
Add only non-whitespace changes
I have my text editor to automatically trim trailing whitespace upon saving a file, and I am contributing to an open source project that has severe problems with trailing whitespace.
...
Difference between a virtual function and a pure virtual function [duplicate]
... class. Derived classes can override virtual functions. Virtual functions called through base class pointers/references will be resolved at run-time. That is, the dynamic type of the object is used instead of its static type:
Derived d;
Base& rb = d;
// if Base::f() is virtual and Derived o...
JavaScript: Class.method vs. Class.prototype.method
... are extending the constructor function prototype, it will be available to all the object instances created with the new keyword, and the context within that function (the this keyword) will refer to the actual object instance where you call it.
Consider this example:
// constructor function
funct...
Determining if a number is either a multiple of ten or within a particular set of ranges
...rite out the pseudo code, but I'm not entirely sure how to write them logically.
13 Answers
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Unrecognized SSL message, plaintext connection? Exception
... you. You can do the same yourself. Indeed HttpURLConnection will automatically do it for you, if you don't specify a port at all.
– Marquis of Lorne
Jun 9 '14 at 23:54
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