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Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
What is Autoloading; How do you use spl_autoload, __autoload and spl_autoload_register?
...
spl_autoload_register() allows you to register multiple functions (or static methods from your own Autoload class) that PHP will put into a stack/queue and call sequentially when a "new Class" is declared.
So for example:
spl_autoload_register('m...
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...
__getattr__ on a module
...
A while ago, Guido declared that all special method lookups on
new-style classes bypass __getattr__ and __getattribute__. Dunder methods had previously worked on modules - you could, for example, use a module as a context manager simply by defining __enter__...
Difference between except: and except Exception as e: in Python
... print e.message, e.args
...
>>> catch()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<stdin>", line 3, in catch
BaseException
Which a bare except does:
>>> def catch():
... try:
... raise BaseException()
... ...
What are the mechanics of short string optimization in libc++?
...ver, I would like to know in more detail how it works in practice, specifically in the libc++ implementation:
2 Answers
...
How do I create a constant in Python?
.... This is the closest equivalent to Java's final. However, it does not actually prevent reassignment:
from typing import Final
a: Final = 1
# Executes fine, but mypy will report an error if you run mypy on this:
a = 2
sha...
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);
...
}
...
What is the best way to compute trending topics or tags?
...
This problem calls for a z-score or standard score, which will take into account the historical average, as other people have mention, but also the standard deviation of this historical data, making it more robust than just using the avera...
Is the list of Python reserved words and builtins available in a library?
...break', 'class', 'continue', 'def',
'del', 'elif', 'else', 'except', 'finally', 'for', 'from', 'global', 'if', 'import',
'in', 'is', 'lambda', 'nonlocal', 'not', 'or', 'pass', 'raise', 'return', 'try',
'while', 'with', 'yield']
If you want to include built-in names as well (Python 3), then c...