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Static class initializer in PHP
...
* @var Singleton
*/
private static $instance;
private function __construct()
{
// Your "heavy" initialization stuff here
}
public static function getInstance()
{
if ( is_null( self::$instance ) )
{
self::$instance = new self();
}
return self::$instance;...
In a django model custom save() method, how should you identify a new object?
...
Updated: With the clarification that self._state is not a private instance variable, but named that way to avoid conflicts, checking self._state.adding is now the preferable way to check.
self.pk is None:
returns True within a new Model object, unless the object...
What is the difference between '/' and '//' when used for division?
...he 2.x line, there is no difference for integers unless you perform a from __future__ import division, which causes Python 2.x to adopt the 3.x behavior.
Regardless of the future import, 5.0 // 2 will return 2.0 since that's the floor division result of the operation.
You can find a detailed descr...
How do I call setattr() on the current module?
...
import sys
thismodule = sys.modules[__name__]
setattr(thismodule, name, value)
or, without using setattr (which breaks the letter of the question but satisfies the same practical purposes;-):
globals()[name] = value
Note: at module scope, the latter is eq...
php stdClass to array
...g functions). "But I already did this" you say. Not exactly - you used json_decode on the array, but you need to encode it with json_encode first.
Requirements
The json_encode and json_decode methods. These are automatically bundled in PHP 5.2.0 and up. If you use any older version there's also a ...
How to create a DataTable in C# and how to add rows?
...e();
dt.Clear();
dt.Columns.Add("Name");
dt.Columns.Add("Marks");
DataRow _ravi = dt.NewRow();
_ravi["Name"] = "ravi";
_ravi["Marks"] = "500";
dt.Rows.Add(_ravi);
To see the structure, or rather I'd rephrase it as schema, you can export it to an XML file by doing the following.
To export only th...
How to send an email from JavaScript
...= require('node-mandrill')('<your API Key>');
function sendEmail ( _name, _email, _subject, _message) {
mandrill('/messages/send', {
message: {
to: [{email: _email , name: _name}],
from_email: 'noreply@yourdomain.com',
subject: _subject,
...
Is there a way to make mv create the directory to be moved to if it doesn't exist?
... this one-liner (in bash):
mkdir --parents ./some/path/; mv yourfile.txt $_
Breaking that down:
mkdir --parents ./some/path
creates the directory (including all intermediate directories), after which:
mv yourfile.txt $_
moves the file to that directory ($_ expands to the last argument passe...
background function in Python
...
Do something like this:
def function_that_downloads(my_args):
# do some long download here
then inline, do something like this:
import threading
def my_inline_function(some_args):
# do some stuff
download_thread = threading.Thread(target=function_t...
How to check BLAS/LAPACK linkage in NumPy and SciPy?
...
The method numpy.show_config() (or numpy.__config__.show()) outputs information about linkage gathered at build time. My output looks like this. I think it means I am using the BLAS/LAPACK that ships with Mac OS.
>>> import numpy as np...