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Is there a function to make a copy of a PHP array to another?
...ewLarsson raises a point in the comments below. PHP has a special feature called "references". They are somewhat similar to pointers in languages like C/C++, but not quite the same. If your array contains references, then while the array itself is passed by copy, the references will still resolve to...
Unique BooleanField value in Django?
... save method of the model and if you've set the boolean to True, make sure all others are set to False.
from django.db import transaction
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one = models.BooleanField()
def save(self, *args, **kwargs):
...
What is the Python equivalent of static variables inside a function?
...
there is only one instance of foo - this one function. all invocations access the same variable.
– Claudiu
Nov 10 '08 at 23:49
124
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Two way/reverse map [duplicate]
...
1
>>> del d['foo']
>>> d['bar']
Traceback (most recent call last):
File "<stdin>", line 7, in <module>
KeyError: 'bar'
I'm sure I didn't cover all the cases, but that should get you started.
...
Where does Scala look for implicits?
...
Implicits in Scala refers to either a value that can be passed "automatically", so to speak, or a conversion from one type to another that is made automatically.
Implicit Conversion
Speaking very briefly about the latter type, if one calls a method m on an object o of a class C, and that class d...
UTF-8 byte[] to String
... You can see in here the java.nio.charset.Charset.availableCharsets() map all the charsets not just the charsets in the StandardCharsets. And if you want to use some other charset and still want to prevent the String constructor from throwing UnsupportedEncodingException you may use java.nio.charse...
How do I move to end of line in Vim?
I know how to generally move around in command mode, specifically, jumping to lines, etc. But what is the command to jump to the end of the line that I am currently on?
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How to JSON serialize sets?
...s.
As shown in the json module docs, this conversion can be done automatically by a JSONEncoder and JSONDecoder, but then you would be giving up some other structure you might need (if you convert sets to a list, then you lose the ability to recover regular lists; if you convert sets to a dictionar...
List all files in one directory PHP [duplicate]
What would be the best way to list all the files in one directory with PHP? Is there a $_SERVER function to do this? I would like to list all the files in the usernames/ directory and loop over that result with a link, so that I can just click the hyperlink of the filename to get there. Thanks!
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How to properly reuse connection to Mongodb across NodeJs application and modules
...lhost:27017";
var _db;
module.exports = {
connectToServer: function( callback ) {
MongoClient.connect( url, { useNewUrlParser: true }, function( err, client ) {
_db = client.db('test_db');
return callback( err );
} );
},
getDb: function() {
return _db;
}
};
To...