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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
...
Getting “Skipping JaCoCo execution due to missing execution data file” upon executing JaCoCo
...ing. 2. In Travis environment variables for my project, had typo in SONART_TOKEN=*****, should have been named SONAR_TOKEN=*****. See Travis docs here, search for or define SONAR_TOKEN in your Repository Settings. After I fixed that, build ran successfully. You may view my gitbhub project in questio...
Effects of changing Django's SECRET_KEY
... salted hmacs or seeding the random engine which impacts:
password reset token
comment form security to protect against forged POST requests
form security
protect against message tampering as the message framework may use cookies to pass messages between views.
protect session data and create rand...
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...
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
...
Convert object to JSON in Android
.../JsonReader.html
Reads a JSON (RFC 4627) encoded value as a stream of tokens. This
stream includes both literal values (strings, numbers, booleans, and
nulls) as well as the begin and end delimiters of objects and arrays.
The tokens are traversed in depth-first order, the same order that
...
