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How to concatenate two strings in C++?
...t to runtime performance. Worst case is, that operator+= performs both a deallocation and an allocation. Heap allocations are among the most expensive operations we commonly do.
– IInspectable
Feb 7 at 12:17
...
How to quickly clear a JavaScript Object?
... issue isn't that things go uncollected, it's that collection runs every X allocations, and takes longer each time. Thus the need to reuse objects.
– levik
Mar 26 '09 at 5:21
...
What function is to replace a substring from a string in C?
..., rep); ++count) {
ins = tmp + len_rep;
}
tmp = result = malloc(strlen(orig) + (len_with - len_rep) * count + 1);
if (!result)
return NULL;
// first time through the loop, all the variable are set correctly
// from here on,
// tmp points to the end of th...
Malloc vs new — different padding
...
IIRC there's one picky point. malloc is guaranteed to return an address aligned for any standard type. ::operator new(n) is only guaranteed to return an address aligned for any standard type no larger than n, and if T isn't a character type then new T[n] i...
Convert a binary NodeJS Buffer to JavaScript ArrayBuffer
...
From ArrayBuffer to Buffer:
function toBuffer(ab) {
var buf = Buffer.alloc(ab.byteLength);
var view = new Uint8Array(ab);
for (var i = 0; i < buf.length; ++i) {
buf[i] = view[i];
}
return buf;
}
...
What happens when a computer program runs?
... but modern OSes with virtual memory tend to load their process images and allocate memory something like this:
+---------+
| stack | function-local variables, return addresses, return values, etc.
| | often grows downward, commonly accessed via "push" and "pop" (but can be
| | ...
UIBarButtonItem with custom image and no border
...UIControlStateNormal];
UIBarButtonItem *random = [[UIBarButtonItem alloc] initWithCustomView:a1];
//? line incomplete ?// imageNamed:@"random.png"] style:UIBarButtonItemStylePlain target:self action:@selector(randomMsg)];
self.navigationItem.rightBarButtonItem = random;
...
Eliminate extra separators below UITableView
...new];
}
or if you prefer,
self.tableView.tableFooterView = [[UIView alloc] initWithFrame:CGRectZero];
Historically in iOS:
Add to the table view controller...
- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section {
// This will create a "invisible"...
Convert UTF-8 encoded NSData to NSString
...ated, you should use -initWithData:encoding:
NSString* newStr = [[NSString alloc] initWithData:theData encoding:NSUTF8StringEncoding];
If the data is null-terminated, you should instead use -stringWithUTF8String: to avoid the extra \0 at the end.
NSString* newStr = [NSString stringWithUTF8String:[t...
How do I add a delay in a JavaScript loop?
...
I believe this has the same memory allocation issues as the answer described in stackoverflow.com/a/3583795/1337392
– Flame_Phoenix
Jul 21 '16 at 10:58
...