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Calling class staticmethod within the class body?
... def stat_func():
return 42
_ANS = stat_func.__func__() # call the staticmethod
def method(self):
ret = Klass.stat_func()
return ret
As an aside, though I suspected that a staticmethod object had some sort of attribute storing the original function, I had no ...
Is there any difference between __DIR__ and dirname(__FILE__) in PHP?
... ; so, no difference on that.
For example, the two following lines :
var_dump(dirname(__FILE__));
var_dump(__DIR__);
Will both give the same output :
string '/home/squale/developpement/tests/temp' (length=37)
But, there are at least two differences :
__DIR__ only exists with PHP >= 5.3...
What are the rules for the “…” token in the context of variadic templates?
...template parameter pack if it appears on the right side of an expression (call this expression pattern for a moment), or it's a pack argument if it appears on left side of the name:
...thing // pack : appears as template arguments
thing... // unpack : appears when consuming the arguments
The ru...
UML class diagram enum
...
They are simply showed like this:
_______________________
| <<enumeration>> |
| DaysOfTheWeek |
|_____________________|
| Sunday |
| Monday |
| Tuesday |
| ... |
|____________________...
Difference between Repository and Service Layer?
... bool Delete(int id);
T Get(int id);
bool SaveChanges();
}
and call Get(id). Repository layer exposes basic CRUD operations.
Service layer exposes business logic, which uses repository. Example service could look like:
public interface IUserService
{
User GetByUserName(string userNa...
What does “abstract over” mean?
...the similarities. We say that we abstract over the differences, but this really means we're integrating by the similarities.
For example, consider a program that takes the sum of the numbers 1, 2, and 3:
val sumOfOneTwoThree = 1 + 2 + 3
This program is not very interesting, since it's not very a...
What is a singleton in C#?
...
A singleton is a class which only allows one instance of itself to be created - and gives simple, easy access to said instance. The singleton premise is a pattern across software development.
There is a C# implementation "Implementing the Singleton Pattern i...
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
...
“is” operator behaves unexpectedly with integers
...3):
The current implementation keeps an
array of integer objects for all
integers between -5 and 256, when you
create an int in that range you
actually just get back a reference to
the existing object. So it should be
possible to change the value of 1. I
suspect the behaviour of Py...
Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...