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What is the function __construct used for?
I have been noticing __construct a lot with classes. I did a little reading and surfing the web, but I couldn't find an explanation I could understand. I am just beginning with OOP.
...
Why do we need virtual functions in C++?
...s to more general). Visa-versa you need an explicit cast, usually a dynamic_cast. Anything else - very prone to undefined behavior so make sure you know what you're doing. To the best of my knowledge, this has not changed since before even C++98.
– Steve314
Jun...
How to refer to relative paths of resources when working with a code repository
...Try to use a filename relative to the current files path. Example for './my_file':
fn = os.path.join(os.path.dirname(__file__), 'my_file')
In Python 3.4+ you can also use pathlib:
fn = pathlib.Path(__file__).parent / 'my_file'
...
JavaScript pattern for multiple constructors
... b= 'some default value';
if (typeof(a)==='string')
this._constructInSomeWay(a, b);
else if (a instanceof MyType)
this._constructInSomeOtherWay(a, b);
}
You can also access arguments as an array-like to get any further arguments passed in.
If you need more complex ar...
add column to mysql table if it does not exist
...
Note that INFORMATION_SCHEMA isn't supported in MySQL prior to 5.0. Nor are stored procedures supported prior to 5.0, so if you need to support MySQL 4.1, this solution isn't good.
One solution used by frameworks that use database migrations is...
What's the difference between dist-packages and site-packages?
... manager into this location:
/usr/lib/python2.7/dist-packages
Since easy_install and pip are installed from the package manager, they also use dist-packages, but they put packages here:
/usr/local/lib/python2.7/dist-packages
From the Debian Python Wiki:
dist-packages instead of site-packag...
Detect network connection type on Android
...er cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
return cm.getActiveNetworkInfo();
}
/**
* Check if there is any connectivity
* @param context
* @return
*/
public static boolean isConnected(Context context){
Networ...
How assignment works with Python list slice?
...
Is a[:] = some_list equivalent to a = some_list[:] or a = some_list?
– jadkik94
May 17 '12 at 10:42
2
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How can you integrate a custom file browser/uploader with CKEditor?
...load" tab will submit a file in the field "upload" - in PHP, that goes to $_FILES['upload']. What CKEditor wants your server to output is a complete JavaScript block:
$output = '<html><body><script type="text/javascript">window.parent.CKEDITOR.tools.callFunction('.$callback.', "'....
Greenlet Vs. Threads
... can i use gevent in this case to read faster import hashlib def checksum_md5(filename): md5 = hashlib.md5() with open(filename,'rb') as f: for chunk in iter(lambda: f.read(8192), b''): md5.update(chunk) return md5.digest()
– Soumya
...