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What does new self(); mean in PHP?
...etInstance method is in a class name MyClass, the following line :
self::$_instance = new self();
Will do the same as :
self::$_instance = new MyClass();
Edit : a couple more informations, after the comments.
If you have two classes that extend each other, you have two situations :
get...
What is the meaning of single and double underscore before an object name?
...owever, nothing special is done with the name itself.
To quote PEP-8:
_single_leading_underscore: weak "internal use" indicator. E.g. from M import * does not import objects whose name starts with an underscore.
Double Underscore (Name Mangling)
From the Python docs:
Any identifier of th...
How to convert an enum type variable to a string?
...ction for each enumeration that performs the conversion to string:
enum OS_type { Linux, Apple, Windows };
inline const char* ToString(OS_type v)
{
switch (v)
{
case Linux: return "Linux";
case Apple: return "Apple";
case Windows: return "Windows";
defau...
boost::flat_map and its performance compared to map and unordered_map
...erformance a lot due to cache hits. I recently found out about boost::flat_map which is a vector based implementation of a map. It doesn't seem to be nearly as popular as your typical map / unordered_map so I haven't been able to find any performance comparisons. How does it compare and what are...
Proper way to declare custom exceptions in modern Python?
... (or pass extra args), do this:
class ValidationError(Exception):
def __init__(self, message, errors):
# Call the base class constructor with the parameters it needs
super(ValidationError, self).__init__(message)
# Now for your custom code...
self.errors = erro...
Git - How to use .netrc file on Windows to save user and password
...onment variable %HOME% (pre-Git 2.0, no longer needed with Git 2.0+)
put a _netrc file in %HOME%
If you are using Windows 7/10, in a CMD session, type:
setx HOME %USERPROFILE%
and the %HOME% will be set to 'C:\Users\"username"'.
Go that that folder (cd %HOME%) and make a file called '_netrc'
N...
Getting SyntaxError for print with keyword argument end=' '
I have this python script where I need to run gdal_retile.py ,
but I get an exception on this line:
14 Answers
...
javac : command not found
...
yes, i am sure. just look at the java-1.6.0-openjdk.x86_64 package information (scroll to the "Files" section) and see that there is no javac in that package. and then look at the OpenJDK Development Environment package.
– ax.
Mar 23 '11 at ...
FragmentPagerAdapter Exists Only In Android.Support.V4.App (and not Android.App)
...pp.Fragment;
namespace Support4
{
[Activity (Label = "@string/fragment_pager_support")]
[IntentFilter (new[]{Intent.ActionMain}, Categories = new[]{ "mono.support4demo.sample" })]
public class FragmentPagerSupport : Activity
//public class FragmentPagerSupport : FragmentActivity
...
How can I safely encode a string in Java to use as a filename?
...ey want, store the filename based on a scheme of my own choosing (eg userId_fileId) and then store the user's filename in a database table. That way you can display it back to the user, store things how you want and you don't compromise security or wipe out other files.
You can also hash the file (...