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A positive lambda: '+[]{}' - What sorcery is this? [duplicate]
...o pass by value instead of reference. The better way would be with static_cast<T>(lvalue) to get a prvalue of type T from an lvalue. "customary to use a generic function called val()": This isn't clear, can you show an example/link of such a val() function?
– Andrew Tom...
What is the significance of 1/1/1753 in SQL Server?
...ith the greater range of datetime2
SELECT CONVERT(VARCHAR, DATEADD(DAY,-5,CAST('1752-09-13' AS DATETIME2)),100)
Returns
Sep 8 1752 12:00AM
One final point with the datetime2 data type is that it uses the proleptic Gregorian calendar projected backwards to well before it was actually invented ...
java: HashMap not working
...s aren't retained at runtime. They are just "syntactic sugar" for explicit casting to save you doing this:
Integer i = (Integer)myMap.get("foo");
To give you an example, this code is perfectly legal:
Map<String, Integer> myMap = new HashMap<String, Integer>();
Map<Integer, String&...
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 pass a single object[] to a params object[]
...
A simple typecast will ensure the compiler knows what you mean in this case.
Foo((object)new object[]{ (object)"1", (object)"2" }));
As an array is a subtype of object, this all works out. Bit of an odd solution though, I'll agree.
...
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.
...
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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How to access environment variable values?
...
print(os.environ.get('KEY_THAT_MIGHT_EXIST'))
# os.getenv is equivalent, and can also give a default value instead of `None`
print(os.getenv('KEY_THAT_MIGHT_EXIST', default_value))
Python default installation on Windows is C:\Python. If you want to find out while running python you can do:
impo...
Using isKindOfClass with Swift
...nted out in @Kevin's answer, the correct way would be to use optional type cast operator as?. You can read more about it on the section Optional Chaining sub section Downcasting.
Edit 2
As pointed on the other answer by user @KPM, using the is operator is the right way to do it.
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