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What does -> mean in Python function definitions?
...
It's a function annotation.
In more detail, Python 2.x has docstrings, which allow you to attach a metadata string to various types of object. This is amazingly handy, so Python 3 extends the feature by allowing you to attach metadata to functions describing their parameters and return ...
The case against checked exceptions
...lly defined by a method signature.
Here fopen requires that you pass it a string (or a char* in the case of C). If you give it something else you get a compile-time error. You didn't follow the protocol - you're not using the API properly.
In some (obscure) languages the return type is part of the...
What are best practices that you use when writing Objective-C and Cocoa? [closed]
...te thread. Make sure to wrap anything that modifies the database for query strings in @synchronize() {} blocks. For short queries just leave things on the main thread for easier convenience.
More SQLite optimization tips are here, though the document appears out of date many of the points are prob...
Location Services not working in iOS 8
...t wanna show custom explanation to the user, just set this key to an empty string.
– nonamelive
Sep 12 '14 at 23:43
7
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Perform .join on value in array of objects
If I have an array of strings, I can use the .join() method to get a single string, with each element separated by commas, like so:
...
Swapping two variable value without using third variable
...y){
int t;
t = *y;
*y = *x;
*x = t;
}
int main(int argc, char* argv[]){
int x = 4;
int y = 5;
int z = pow(2,28);
while ( z-- ){
# ifdef USE_XOR
xorSwap(&x,&y);
# else
tempSwap(&x, &y);
# endif
}
retu...
How to vertically center a container in Bootstrap?
...rial, sans-serif;
}
WORKING DEMO.
Also, to prevent unexpected issues in extra small screens, you can reset the height of the pseudo-element to auto or 0 or change its display type to none if needed so:
@media (max-width: 768px) {
.vertical-center:before {
height: auto;
/* Or */
di...
How to create a drop-down list?
...n = findViewById(R.id.spinner1);
//create a list of items for the spinner.
String[] items = new String[]{"1", "2", "three"};
//create an adapter to describe how the items are displayed, adapters are used in several places in android.
//There are multiple variations of this, but this is the basic var...
PHP: How to send HTTP response code?
...");
Note: According to the HTTP RFC, the reason phrase can be any custom string (that conforms to the standard), but for the sake of client compatibility I do not recommend putting a random string there.
Note: php_sapi_name() requires PHP 4.0.1
3rd argument to header function (PHP >= 4.3)
Th...
How does one write code that best utilizes the CPU cache to improve performance?
...rewriting techniques known as tiling or blocking all strive to avoid those extra memory fetches.
While there are some rules of thumb for this rewrite exercise, you typically have to carefully consider loop carried data dependencies, to ensure that you don't affect the semantics of the program.
The...