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What does asterisk * mean in Python? [duplicate]
... have a special meaning in Python as it does in C? I saw a function like this in the Python Cookbook:
5 Answers
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What exactly are late static bindings in PHP?
... same rules of inheritance. self always resolves to the class in which it is used. This means that if you make a method in a parent class and call it from a child class, self will not reference the child as you might expect.
Late static binding introduces a new use for the static keyword, which a...
Should I use the datetime or timestamp data type in MySQL?
...d to track changes to records, and are often updated every time the record is changed. If you want to store a specific value you should use a datetime field.
If you meant that you want to decide between using a UNIX timestamp or a native MySQL datetime field, go with the native format. You can do c...
How do I check for nulls in an '==' operator overload without infinite recursion?
...
Use ReferenceEquals:
Foo foo1 = null;
Foo foo2 = new Foo();
Assert.IsFalse(foo1 == foo2);
public static bool operator ==(Foo foo1, Foo foo2) {
if (object.ReferenceEquals(null, foo1))
return object.ReferenceEquals(null, foo2);
return foo1.Equals(foo2);
}
...
How to read and write into file using JavaScript?
...
For completeness, the OP does not state he is looking to do this in a browser (if he is, as has been stated, it is generally not possible)
However javascript per se does allow this; it can be done with server side javascript.
See this documentation on the Javascript...
How to make an enum conform to a protocol in Swift?
...
This is my attempt:
protocol ExampleProtocol {
var simpleDescription: String { get }
mutating func adjust()
}
enum ExampleEnum : ExampleProtocol {
case Base, Adjusted
var simpleDescription: String {
r...
Remove duplicate rows in MySQL
...
A really easy way to do this is to add a UNIQUE index on the 3 columns. When you write the ALTER statement, include the IGNORE keyword. Like so:
ALTER IGNORE TABLE jobs
ADD UNIQUE INDEX idx_name (site_id, title, company);
This will drop all the d...
How to Unit test with different settings in Django?
Is there any simple mechanism for overriding Django settings for a unit test? I have a manager on one of my models that returns a specific number of the latest objects. The number of objects it returns is defined by a NUM_LATEST setting.
...
What is Autoloading; How do you use spl_autoload, __autoload and spl_autoload_register?
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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_reg...
Why do you have to link the math library in C?
...io.h have implementations in libc.so (or libc.a for static linking), which is linked into your executable by default (as if -lc were specified). GCC can be instructed to avoid this automatic link with the -nostdlib or -nodefaultlibs options.
The math functions in math.h have implementations in lib...