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How to get the return value from a thread in python?
...ram in param_list] The order will be maintained, and exiting the with will allow result collection. [f.result() for f in futures]
– jayreed1
Jun 4 at 21:29
...
C# operator overload for `+=`?
...nguage has its own operators list, which are compiled in a special method calls, and CLR itself doesn't know anything about operators. So let's see what exactly stays behind the + and += operators.
See this simple code:
Decimal d = 10M;
d = d + 10M;
Console.WriteLine(d);
Let view the IL-code for...
Why do we need extern “C”{ #include } in C++?
...
C and C++ are superficially similar, but each compiles into a very different set of code. When you include a header file with a C++ compiler, the compiler is expecting C++ code. If, however, it is a C header, then the compiler expects the data cont...
Does python have an equivalent to Java Class.forName()?
...takes a fully qualified class name and returns the class, however you have all the pieces needed to build that, and you can connect them together.
One bit of advice though: don't try to program in Java style when you're in python.
If you can explain what is it that you're trying to do, maybe we ca...
How to get the request parameters in Symfony 2?
...
The naming is not all that intuitive:
use Symfony\Component\HttpFoundation\Request;
public function updateAction(Request $request)
{
// $_GET parameters
$request->query->get('name');
// $_POST parameters
$request->r...
Understanding repr( ) function in Python
...gt;>> x
'foo'
So the name x is attached to 'foo' string. When you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the s...
Iterate over object attributes in python
...foo = 1
... bar = 'hello'
... def func(self):
... return 'call me'
...
>>> obj = Cls()
calling dir on the object gives you back all the attributes of that object, including python special attributes. Although some object attributes are callable, such as methods.
>>&...
How to suppress “unused parameter” warnings in C?
...
I usually write a macro like this:
#define UNUSED(x) (void)(x)
You can use this macro for all your unused parameters. (Note that this works on any compiler.)
For example:
void f(int x) {
UNUSED(x);
...
}
...
Why use prefixes on member variables in C++ classes
...before a capital letter in a word is reserved.
For example:
_Foo
_L
are all reserved words while
_foo
_l
are not. There are other situations where leading underscores before lowercase letters are not allowed. In my specific case, I found the _L happened to be reserved by Visual C++ 2005 and ...
When is “i += x” different from “i = i + x” in Python?
...
This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used fo...