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When should I make explicit use of the `this` pointer?
...ired.
Consider the following code:
template<class T>
struct A {
int i;
};
template<class T>
struct B : A<T> {
int foo() {
return this->i;
}
};
int main() {
B<int> b;
b.foo();
}
If you omit this->, the compiler does not know how to trea...
Sending Arguments To Background Worker?
Let's say I want to sent an int parameter to a background worker, how can this be accomplished?
8 Answers
...
C++ Tuple vs Struct
...e first start with a default struct and a tuple.
struct StructData {
int X;
int Y;
double Cost;
std::string Label;
bool operator==(const StructData &rhs) {
return std::tie(X,Y,Cost, Label) == std::tie(rhs.X, rhs.Y, rhs.Cost, rhs.Label);
}
bool operator<...
How many constructor arguments is too many?
...
Two design approaches to consider
The essence pattern
The fluent interface pattern
These are both similar in intent, in that we slowly build up an intermediate object, and then create our target object in a single step.
An example of the fluent interface in action would be:
public class...
Parse date string and change format
...
convert string to datetime object
from datetime import datetime
s = "2016-03-26T09:25:55.000Z"
f = "%Y-%m-%dT%H:%M:%S.%fZ"
out = datetime.strptime(s, f)
print(out)
output:
2016-03-26 09:25:55
...
How do I find out which process is locking a file using .NET?
...
Good point. This wasn't a problem with the deployment script (used internally), but would be in other scenarios.
– orip
Jan 5 '12 at 10:54
...
Connecting overloaded signals and slots in Qt 5
...m having trouble getting to grips with the new signal/slot syntax (using pointer to member function) in Qt 5, as described in New Signal Slot Syntax . I tried changing this:
...
Hidden features of C
...
Function pointers. You can use a table of function pointers to implement, e.g., fast indirect-threaded code interpreters (FORTH) or byte-code dispatchers, or to simulate OO-like virtual methods.
Then there are hidden gems in the stand...
Non-static variable cannot be referenced from a static context
...ecific instance. For methods, this usually are global helper methods (like Integer.parseInt()). For fields, it's usually constants (like car types, i.e. something where you have a limited set which doesn't change often).
To solve your problem, you need to instantiate an instance (create an object) ...
Which is better, return value or out parameter?
...else, it stops the caller from having to declare the variable separately:
int foo;
GetValue(out foo);
vs
int foo = GetValue();
Out values also prevent method chaining like this:
Console.WriteLine(GetValue().ToString("g"));
(Indeed, that's one of the problems with property setters as well, a...