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What are the differences between Rust's `String` and `str`?
...he executable and loaded into memory when the program runs.
Inside a heap allocated String: String dereferences to a &str view of the String's data.
On the stack: e.g. the following creates a stack-allocated byte array, and then gets a view of that data as a &str:
use std::str;
let x:...
Optimising Android application before release [closed]
...
Track and squash allocations. The more you allocate, the more often the garbage collector will need to run, stopping your process from doing anything else for relatively long periods of time, such as 100ms or so.
The best tool I know for th...
How to “log in” to a website using Python's Requests module?
...a form with CSRF Protection (as used in Flask-WTF forms). Check if a csrf_token is required as a hidden field and add it to the payload with the username and password:
import requests
from bs4 import BeautifulSoup
payload = {
'email': 'email@example.com',
'password': 'passw0rd'
}
wi...
Stack Memory vs Heap Memory [duplicate]
...thing similar.
Heap memory is much as rskar says. In general, C++ objects allocated with new, or blocks of memory allocated with the likes of malloc end up on the heap. Heap memory almost always must be manually freed, though you should really use a smart pointer class or similar to avoid needing t...
Animate change of view controllers without using navigation controller stack, subviews or modal cont
...ngWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
MyViewController *vc = [[MyViewContoller alloc] init...];
self.transitionController = [[TransitionController alloc] initWithViewController:vc];
self.window.roo...
Why start an ArrayList with an initial capacity?
...ity. If you don't do this, the internal array will have to be repeatedly reallocated as the list grows.
The larger the final list, the more time you save by avoiding the reallocations.
That said, even without pre-allocation, inserting n elements at the back of an ArrayList is guaranteed to take to...
How to use enums in C++
...++ developer might call a 'dot operator' the C++ compiler can only call a 'token'. When it gets that hard to understand the error messages there is something wrong with the language I think.
– Travis
Jul 6 '16 at 19:27
...
What is the easiest way to ignore a JPA field during persistence?
...e in Jackson) use @JsonInclude :
@JsonInclude()
@Transient
private String token;
TIP:
You can also use JsonInclude.Include.NON_NULL and hide fields in JSON during deserialization when token == null:
@JsonInclude(JsonInclude.Include.NON_NULL)
@Transient
private String token;
...
How to show “Done” button on iPhone number pad
...oad
{
[super viewDidLoad];
UIToolbar* numberToolbar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 50)];
numberToolbar.barStyle = UIBarStyleBlackTranslucent;
numberToolbar.items = @[[[UIBarButtonItem alloc]initWithTitle:@"Cancel" style:UIBarButtonItemStyleBordered target:se...
How do I profile memory usage in Python?
...
Python 3.4 includes a new module: tracemalloc. It provides detailed statistics about which code is allocating the most memory. Here's an example that displays the top three lines allocating memory.
from collections import Counter
import linecache
import os
import ...