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Count the items from a IEnumerable without iterating?
...enumerator.MoveNext())
result++;
}
return result;
So it tries to cast to ICollection<T>, which has a Count property, and uses that if possible. Otherwise it iterates.
So your best bet is to use the Count() extension method on your IEnumerable<T> object, as you will get the bes...
How to delete the contents of a folder?
...
If you're working with a very large directory, and particularly a network directory on windows, and you can control the environment in which this program runs, it might be worth using Py3.5's "os.scandir(folder)" function instead of listdir. The syntax is quite different ...
How to get file creation & modification date/times in Python?
...on date in a cross-platform way is easy - just call os.path.getmtime(path) and you'll get the Unix timestamp of when the file at path was last modified.
Getting file creation dates, on the other hand, is fiddly and platform-dependent, differing even between the three big OSes:
On Windows, a file'...
How to delete a file or folder?
...os.rmdir() removes an empty directory.
shutil.rmtree() deletes a directory and all its contents.
Path objects from the Python 3.4+ pathlib module also expose these instance methods:
pathlib.Path.unlink() removes a file or symbolic link.
pathlib.Path.rmdir() removes an empty directory.
...
TypeScript: Creating an empty typed container array
...e declaration.
The advantage of using a type assertion (sometimes called a cast, but it's not really a cast in TypeScript) works for any expression, so it can be used even when no variable is declared. There are two syntaxes for type assertions, but only the latter will work in combination with JSX ...
Struggling trying to get cookie out of response with HttpClient in .net 4.5
...com");
IEnumerable<Cookie> responseCookies = cookies.GetCookies(uri).Cast<Cookie>();
foreach (Cookie cookie in responseCookies)
Console.WriteLine(cookie.Name + ": " + cookie.Value);
Console.ReadLine();
shar...
What does T&& (double ampersand) mean in C++11?
...t[]> ptr2{ptr1};// compile error: no copy ctor.
// So we must first cast ptr1 to an rvalue
std::unique_ptr<int[]> ptr2{std::move(ptr1)};
std::unique_ptr<int[]> TakeOwnershipAndAlter(std::unique_ptr<int[]> param,\
int size)
{
for (auto i = 0; i < size; ++i) {...
Rename multiple files in a directory in Python [duplicate]
... Im getting an error from windows saying it cant find the file, and it's not doing anything...any tips?
– Jeff
May 3 '10 at 15:49
5
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Redefining NULL
...es not require null pointers to be at the machine's address zero. HOWEVER, casting a 0 constant to a pointer value must result in a NULL pointer (§6.3.2.3/3), and evaluating the null pointer as a boolean must be false. This can be a bit awkward if you really do want a zero address, and NULL is not ...
What is the iPad user agent?
...is using iPhone OS, but with a different screen resolution from the iPhone and iPod touch. So many sites may have to change their user agent detection to adapt to the iPad.
...