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Python class inherits object
...between Python 2 and 3, no reason. In Python 2, many reasons.
Python 2.x story:
In Python 2.x (from 2.2 onwards) there's two styles of classes depending on the presence or absence of object as a base-class:
"classic" style classes: they don't have object as a base class:
>>> class C...
Is there a difference between “==” and “is”?
...gt;>> "a" is "a"
True
>>> "aa" is "a" * 2
True
>>> x = "a"
>>> "aa" is x * 2
False
>>> "aa" is intern(x*2)
True
Please see this question as well.
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String Concatenation using '+' operator
...
It doesn't - the C# compiler does :)
So this code:
string x = "hello";
string y = "there";
string z = "chaps";
string all = x + y + z;
actually gets compiled as:
string x = "hello";
string y = "there";
string z = "chaps";
string all = string.Concat(x, y, z);
(Gah - intervening ...
What does functools.wraps do?
...it on StackOverflow for future reference: what does functools.wraps do, exactly?
6 Answers
...
Populating a razor dropdownlist from a List in MVC
...ar roles = dbUserRoles
.GetRoles()
.Select(x =>
new SelectListItem
{
Value = x.UserRoleId.ToString(),
Text = x.UserRole
}...
Understanding CUDA grid dimensions, block dimensions and threads organization (simple explanation) [
How are threads organized to be executed by a GPU?
2 Answers
2
...
Why is using “for…in” for array iteration a bad idea?
...
for (var i = 0; i < a.length; i++) {
// Iterate over numeric indexes from 0 to 5, as everyone expects.
console.log(a[i]);
}
/* Will display:
undefined
undefined
undefined
undefined
undefined
5
*/
can sometimes be totally different from the other:
...
What's the difference between VARCHAR and CHAR?
...
VARCHAR is variable-length.
CHAR is fixed length.
If your content is a fixed size, you'll get better performance with CHAR.
See the MySQL page on CHAR and VARCHAR Types for a detailed explanation (be sure to also read the comments).
...
Can C++ code be valid in both C++03 and C++11 but do different things?
...ll now implicitly move them when possible.
On the negative side, several examples are listed in the appendix C of the standard. Even though there are many more negative ones than positive, each one of them is much less likely to occur.
String literals
#define u8 "abc"
const char* s = u8"def"; // Pr...
How to calculate the number of occurrence of a given character in each row of a column of strings?
I have a data.frame in which certain variables contain a text string. I wish to count the number of occurrences of a given character in each individual string.
...