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differentiate null=True, blank=True in django
...y string ('').
A few examples:
models.DateTimeField(blank=True) # raises IntegrityError if blank
models.DateTimeField(null=True) # NULL allowed, but must be filled out in a form
Obviously, Those two options don't make logical sense to use (though there might be a use case for null=True, blank=F...
A generic list of anonymous class
...
It does seem an inconsistency in Visual Studio, that intellisense isn't more helpful in uncovering missing includes of assemblies with referenced extension methods (same as referenced types).
– LOAS
Jan 4 '12 at 12:21
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std::shared_ptr thread safety explained
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As others have pointed out, you've got it figured out correctly regarding your original 3 questions.
But the ending part of your edit
Calling reset() in thread IV will delete previous instance of A class created in first thread and replace i...
How should I use try-with-resources with JDBC?
...don't have to refer to a separate method:
public List<User> getUser(int userId) {
String sql = "SELECT id, username FROM users WHERE id = ?";
List<User> users = new ArrayList<>();
try (Connection con = DriverManager.getConnection(myConnectionURL);
PreparedStat...
How to use SharedPreferences in Android to store, fetch and edit values [closed]
...nces gives me the following error: The method getSharedPreferences(String, int) is undefined for the type MyActivity
– Si8
Jul 29 '13 at 19:14
17
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How do I find which program is using port 80 in Windows? [duplicate]
... = $g[2].Value } -PassThru |
Add-Member @{ LocalPort = [int]$g[3].Value } -PassThru |
Add-Member @{ RemoteAddress = $g[4].Value } -PassThru |
Add-Member @{ RemotePort = $g[5].Value } -PassThru |
Add-Member @{ State = $g[6].Value...
RSA Public Key format
...to -----BEGIN RSA PUBLIC KEY----- and expect that it will be sufficient to convert from one format to another (which is what you've done in your example).
This article has a good explanation about both formats.
What you get in an RSA PUBLIC KEY is closer to the content of a PUBLIC KEY, but you nee...
How to read and write INI file with Python3?
...nfigparser
config = configparser.ConfigParser()
config.read('FILE.INI')
print(config['DEFAULT']['path']) # -> "/path/name/"
config['DEFAULT']['path'] = '/var/shared/' # update
config['DEFAULT']['default_message'] = 'Hey! help me!!' # create
with open('FILE.INI', 'w') as configfile: ...
How to enumerate an enum with String type?
...ase diamonds = "♦"; case clubs = "♣" }
Then the following code will print all possible values:
Suit.allCases.forEach {
print($0.rawValue)
}
Compatibility with earlier Swift versions (3.x and 4.x)
If you need to support Swift 3.x or 4.0, you may mimic the Swift 4.2 implementation by adding...
How to remove from a map while iterating it?
...nalogy, it has always been perfectly legitimate to delete p where p is a pointer-to-constant. Constness does not constrain lifetime; const values in C++ can still stop existing.
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