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What is move semantics?
...:
#include <cstring>
#include <algorithm>
class string
{
char* data;
public:
string(const char* p)
{
size_t size = std::strlen(p) + 1;
data = new char[size];
std::memcpy(data, p, size);
}
Since we chose to manage the memory ourselves, we need...
How do I trim whitespace from a string?
... Hello ")
' Hello'
Also, note that str.strip() removes other whitespace characters as well (e.g. tabs and newlines). To remove only spaces, you can specify the character to remove as an argument to strip, i.e.:
>>> " Hello\n".strip(" ")
'Hello\n'
...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
....h>
#include <stddef.h>
int main(void)
{
struct foo {
char c;
int x;
} __attribute__((packed));
struct foo arr[2] = { { 'a', 10 }, {'b', 20 } };
int *p0 = &arr[0].x;
int *p1 = &arr[1].x;
printf("sizeof(struct foo) = %d\n", (int)sizeof(str...
Why historically do people use 255 not 256 for database field magnitudes?
You often see database fields set to have a magnitude of 255 characters, what is the traditional / historic reason why? I assume it's something to do with paging / memory limits, and performance but the distinction between 255 and 256 has always confused me.
...
“sending 'const NSString *' to parameter of type 'NSString *' discards qualifiers” warning
...he term on its right only if there's nothing on its left side (e. g. const char * and a char const * are non-const pointers to const char, but char *const is a const pointer to non-const char).
– user529758
Oct 11 '12 at 4:29
...
Why is “while ( !feof (file) )” always wrong?
...e is again std::cin, just as before.
POSIX, write(2) to flush a buffer:
char const * p = buf;
ssize_t n = bufsize;
for (ssize_t k = bufsize; (k = write(fd, p, n)) > 0; p += k, n -= k) {}
if (n != 0) { /* error, failed to write complete buffer */ }
The result we use here is k, the numb...
How to handle Objective-C protocols that contain properties?
...hInteger:(factor*amount)];
}
// <<
@end
int main(int argc, const char * argv[])
{
@autoreleasepool {
Person *duncan=[[Person alloc]initConforming];
duncan.firstname=@"Duncan";
duncan.lastname=@"Smith";
[Viewer printLargeDescription:duncan];
S...
LINQ equivalent of foreach for IEnumerable
...d evaluating Funcs
var evaluatedObservable = observable.ToEnumerable().Select(func => func()).ToList();
//Win
Assert.That(evaluatedObservable,
Is.EquivalentTo(values.ToList()));
}
The following fails with the error:
Expected: equivalent to < 0, 1, 2, 3, 4, 5, 6, 7, 8, ...
Best way to parseDouble with comma as decimal separator?
... The problem with NumberFormat is that it will silently ignore invalid characters. So if you try to parse "1,23abc" it will happily return 1.23 without indicating to you that the passed-in String contained non-parsable characters. In some situations that might actually be desirable, but I don't ...
How to show a confirm message before delete?
...message on clicking delete (this maybe a button or an image). If the user selects ' Ok ' then delete is done, else if ' Cancel ' is clicked nothing happens.
...