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How to set conditional breakpoints in Visual Studio?
...t a breakpoint.
Right-Click over the breakpoint, and in the popup menu you select an option that suites you.
These options are as follows:
You can set a condition, based on a code expression that you supply (select Condition from the popup menu). For instance, you can specify that foo == 8 or s...
How can I check whether a option already exist in select by JQuery
How can I check whether a option already exist in select by JQuery?
8 Answers
8
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How to force LINQ Sum() to return 0 while source collection is empty
...word
&& l.Property.PropertyId == PropertyId)
.Select(l => l.Amount)
.DefaultIfEmpty(0)
.Sum();
This way, your query will only select the Amount field. If the collection is empty, it will return one element with the value of 0 and then the sum will ...
Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_
...;
#include <chrono>
#include <x86intrin.h>
int main(int argc, char* argv[]) {
using namespace std;
uint64_t size=1<<20;
uint64_t* buffer = new uint64_t[size/8];
char* charbuffer=reinterpret_cast<char*>(buffer);
for (unsigned i=0;i<size;++i) charbuffer[i]=...
What's the best way to check if a file exists in C?
...t; // stat
#include <stdbool.h> // bool type
bool file_exists (char *filename) {
struct stat buffer;
return (stat (filename, &buffer) == 0);
}
and call it like this:
#include <stdio.h> // printf
int main(int ac, char **av) {
if (ac != 2)
return 1;
...
How should one use std::optional?
...
@Rapptz Line 256: union storage_t { unsigned char dummy_; T value_; ... } Line 289: struct optional_base { bool init_; storage_t<T> storage_; ... } How is that not "a T and a bool"? I completely agree the implementation is very tricky and nontrivial, but conceptua...
Android Spinner : Avoid onItemSelected calls during initialization
...droid application with a Spinner and a TextView . I want to display the selected item from the Spinner's drop down list in the TextView. I implemented the Spinner in the onCreate method so when I'm running the program, it shows a value in the TextView (before selecting an item from the drop d...
Java: splitting a comma-separated string but ignoring commas in quotes
...\"comma: ,\"", all you need to do is strip off the extraneous double quote characters.
– Paul Hanbury
Nov 18 '09 at 17:41
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What is the purpose of std::make_pair vs the constructor of std::pair?
...two = make_pair (10.5,'A'); // ok: implicit conversion from pair<double,char>
Aside from the implicit conversion bonus of it, if you didn't use make_pair you'd have to do
one = pair<int,int>(10,20)
every time you assigned to one, which would be annoying over time...
...
Why is it impossible to build a compiler that can determine if a C++ function will change the value
... /* modify variable */
variable = 1;
}
}
int main(int argc, char **argv) {
if (modifies_variable(f, variable)) {
printf("Modifies variable\n");
} else {
printf("Does not modify variable\n");
}
return 0;
}
...