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What is the difference between char array and char pointer in C?
...nal length of the array, if known, for example, if the array is statically allocated), the details can be found in the standard. And at the level of runtime no difference between them (in assembler, well, almost, see below).
Also, there is a related question in the C FAQ:
Q: What is the differe...
Java: how to initialize String[]?
.../ <--initialized statement
You need to initialize the array so it can allocate the correct memory storage for the String elements before you can start setting the index.
If you only declare the array (as you did) there is no memory allocated for the String elements, but only a reference handle...
std::function vs template
...pe-erasure magic for the storage. Generally, this implies a dynamic memory allocation (by default through a call to new). It's well known that this is a quite costly operation.
The standard (20.8.11.2.1/5) encorages implementations to avoid the dynamic memory allocation for small objects which, tha...
What is the overhead of creating a new HttpClient per call in a WebAPI client?
... new HttpClientHandler(); //never dispose this
HttpClient GetClient(string token)
{
//client code can dispose these HttpClient instances
return new HttpClient(_sharedHandler, disposeHandler: false)
{
DefaultRequestHeaders =
{
Authorization = new Authen...
What is the default height of UITableViewCell?
...
If you want to calculate this on the fly, just allocate a dummy table cell and read off its height
UITableViewCell *cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"Cell"];
int height = cell.frame.size.height ;
This way you de...
Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
...
[[NSObject]alloc]init] does not equal TRUE or YES. So testing for object initialization with if ([[NSObject]alloc]init]==TRUE) will fail. I've never been comfortable with a Language defining a singular "true" value when in fact any non ...
Rails params explained?
... seeing that in rails4. For instance, {"_method"=>"put", "authenticity_token"=>"gubHya6uQrQLjPRXhOC0RUuCRdn7NFr6CeKrbRfBSHI=", "ripe"=>"true", "action"=>"update", "controller"=>"apples", "id"=>"4"}. Forgive me if I'm wrong, I'm a rails beginner. According to your note, I should ...
Why aren't superclass __init__ methods automatically invoked?
...ar (it is called during the creation of a new object, after that object is allocated, to set member variables on the new object), and is almost always the place to implement functionality that in other languages you would put in a constructor. So just call it a constructor!
– B...
How to Rotate a UIImage 90 degrees?
...eImage = [UIImage imageNamed:imgname];
UIImage * portraitImage = [[UIImage alloc] initWithCGImage: landscapeImage.CGImage
scale: 1.0
orientation: UIImageOrientationRight];
Note: As Brainware said th...
How do I convert a Vector of bytes (u8) to a string
...("result: {}", s);
}
The conversion is in-place, and does not require an allocation. You can create a String from the string slice if necessary by calling .to_owned() on the string slice (other options are available).
The library reference for the conversion function:
std::str::from_utf8
...