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dynamic_cast and static_cast in C++
...lass Derived2 : public Base {};
class ReDerived : public Derived {};
void test( Base & base )
{
dynamic_cast<Derived&>(base);
}
int main() {
Base b;
Derived d;
Derived2 d2;
ReDerived rd;
test( b ); // throw: b is not a Derived object
test( d ); // ok
test...
Detect if called through require or directly by command line
...a module');
}
See documentation for this here: https://nodejs.org/docs/latest/api/modules.html#modules_accessing_the_main_module
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Checking network connection
...ome Internet server, then we indeed have connectivity. However, for the fastest and most reliable approach, all solutions should comply with the following requirements, at the very least:
Avoid DNS resolution (we will need an IP that is well-known and guaranteed to be available for most of the time...
Calling parent class __init__ with multiple inheritance, what's the right way?
...ing super() leads to greater flexibility for subclasses.
In the direct call approach, C.__init__ can call both A.__init__ and B.__init__.
When using super(), the classes need to be designed for cooperative multiple inheritance where C calls super, which invokes A's code which will also call supe...
Include constant in string without concatenating
...er indirect variations, unnecessarily creating functions, yours is the shortest and to the point solution that relies on variable functions, underrated and very infrequently used feature of PHP. Out of this whole thread I went with YOUR particular solution. I wish I could +1 it more than once.
...
Javascript: Round up to the next multiple of 5
...%5<3 ? (x%5===0 ? x : Math.floor(x/5)*5) : Math.ceil(x/5)*5 }
And the tests:
for (var x=40; x<51; x++) {
console.log(x+"=>", x%5<3 ? (x%5===0 ? x : Math.floor(x/5)*5) : Math.ceil(x/5)*5)
}
// 40 => 40
// 41 => 40
// 42 => 40
// 43 => 45
// 44 => 45
// 45 => 45
// 4...
Change one value based on another value in pandas
...lowing code might be helpful for you.
import pandas
df = pandas.read_csv("test.csv")
df.loc[df.ID == 103, 'FirstName'] = "Matt"
df.loc[df.ID == 103, 'LastName'] = "Jones"
As mentioned in the comments, you can also do the assignment to both columns in one shot:
df.loc[df.ID == 103, ['FirstName', ...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
...kets from the server.
I spent several days to solve this problem. I have tested many approaches that have been mentioned in different web sites, but non of them worked. Finally I changed my code and found out what was the problem. I'll try to tell you about different approaches and sum them up her...
DirectX SDK (June 2010) Installation Problems: Error Code S1023
...y run Windows Update and it will update the redistributables back to the latest version.
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Difference between passing array and array pointer into function in C
...
No, there is no difference between them. To test I wrote this C code in Dev C++(mingw) compiler:
#include <stdio.h>
void function(int* array) {
int a =5;
}
void main() {
int array[]={2,4};
function(array);
getch();
}
When I disassemble ...