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How do I concatenate or merge arrays in Swift?
...ith Sequence's flatMap(_:) method
Swift provides a flatMap(_:) method for all types that conform to Sequence protocol (including Array). flatMap(_:) has the following declaration:
Returns an array containing the concatenated results of calling the given transformation with each element of this ...
What is the most efficient string concatenation method in python?
... idiomatic and thus easier for other python programmers to understand.
Finally, the golden rule of optimization: don't optimize unless you know you need to, and measure rather than guessing.
You can measure different methods using the timeit module. That can tell you which is fastest, instead of r...
How do I pass parameters into a PHP script through a webpage?
I am calling a PHP script whenever a webpage loads. However, there is a parameter that the PHP script needs to run (which I normally pass through the command line when I am testing the script).
...
What are the calling conventions for UNIX & Linux system calls (and user-space functions) on i386 an
Following links explain x86-32 system call conventions for both UNIX (BSD flavor) & Linux:
4 Answers
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How to limit the maximum value of a numeric field in a Django model?
...ormer can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a certain range, e.g. 0.0-5.0 ?
...
What is the use of static variable in C#? When to use it? Why can't I declare the static variable in
...
A static variable shares the value of it among all instances of the class.
Example without declaring it static:
public class Variable
{
public int i = 5;
public void test()
{
i = i + 5;
Console.WriteLine(i);
}
}
public class Exercise
{
...
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...
Comma in C/C++ macro
...his is also a problem for square brackets and braces, even though those usually occur as balanced pairs.) You can enclose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which pr...
List of foreign keys and the tables they reference
...key is described in the columns r_owner and r_constraint_name of the table ALL_CONSTRAINTS. This will give you the info you want:
SELECT a.table_name, a.column_name, a.constraint_name, c.owner,
-- referenced pk
c.r_owner, c_pk.table_name r_table_name, c_pk.constraint_name r_pk
FROM...
Why does the MongoDB Java driver use a random number generator in a conditional?
...k && Math.random() <= 0.1)
return res;
The commit that originally introduced this logic had
if (_ok == true) {
_logger.log( Level.WARNING , "Server seen down: " + _addr, e );
} else if (Math.random() < 0.1) {
_logger.log( Level.WARNING , "Server seen down: " + _addr );
}
—a...