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Are tuples more efficient than lists in Python?
...les can be reused instead of copied.
3) Tuples are compact and don't over-allocate.
4) Tuples directly reference their elements.
Tuples can be constant folded
Tuples of constants can be precomputed by Python's peephole optimizer or AST-optimizer. Lists, on the other hand, get built-up from scra...
presentViewController and displaying navigation bar
...troller you want:
MyViewController *myViewController = [[MyViewController alloc] initWithNibName:nil bundle:nil];
UINavigationController *navigationController =
[[UINavigationController alloc] initWithRootViewController:myViewController];
//now present this navigation controller modally
[sel...
General guidelines to avoid memory leaks in C++ [closed]
...rams? How do I figure out who should free memory that has been dynamically allocated?
29 Answers
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What does “dereferencing” a pointer mean?
... // Note earlier ++p and + 2 here => sizes[3]
Pointers to dynamically allocated memory
Sometimes you don't know how much memory you'll need until your program is running and sees what data is thrown at it... then you can dynamically allocate memory using malloc. It is common practice to store ...
What's a simple way to get a text input popup dialog box on an iPhone
...will not need a private API for this.
UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Alert" message:@"This is an example alert!" delegate:self cancelButtonTitle:@"Hide" otherButtonTitles:nil];
alert.alertViewStyle = UIAlertViewStylePlainTextInput;
[alert show];
[alert release];
This r...
Fatal Error: Allowed Memory Size of 134217728 Bytes Exhausted (CodeIgniter + XML-RPC)
...
The memory allocation for PHP can be adjusted permanently, or temporarily.
Permanently
You can permanently change the PHP memory allocation two ways.
If you have access to your php.ini file, you can edit the value for memory_limit to...
UITapGestureRecognizer - single tap and double tap
...
UITapGestureRecognizer *singleTap = [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(doSingleTap)] autorelease];
singleTap.numberOfTapsRequired = 1;
[self.view addGestureRecognizer:singleTap];
UITapGestureRecognizer *doubleTap = [[[UITapGestureRecognizer alloc] in...
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
...
How can I use pointers in Java?
...ystem will throw an exception (OutOfMemoryError) when you call new and the allocator cannot allocate the requested cell. This is very rare and usually results from run-away recursion.
Note that, from a language point of view, abandoning objects to the garbage collector are not errors at all. It is ...