大约有 23,000 项符合查询结果（耗时：0.0439秒） [XML]
Create a GUID in Java
...en an (unverified !!) claim that someone did run into problems with random-based UUIDs not being unique.
– Stephen C
Sep 14 '17 at 1:29
add a comment
|
...
Convert hex string to int in Python
...
Without the 0x prefix, you need to specify the base explicitly, otherwise there's no way to tell:
x = int("deadbeef", 16)
With the 0x prefix, Python can distinguish hex and decimal automatically.
>>> print int("0xdeadbeef", 0)
3735928559
>>> print in...
Fast permutation -> number -> permutation mapping algorithms
... pattern in the weight is of course that the weight is w = b^k, with b the base of the number and k the index of the digit. (I will always count digits from the right and starting at index 0 for the rightmost digit. Likewise when I talk about the 'first' digit I mean the rightmost.)
The reason why ...
Why do people hate SQL cursors so much? [closed]
...n is the obvious internal cursor implementation.
Using higher-level "set-based operators" bundles the cursor results into a single result set, meaning less API back-and-forth.
Cursors predate modern languages that provide first-class collections. Old C, COBOL, Fortran, etc., had to process rows ...
Why should I use document based database instead of relational database?
Why should I use document based database like CouchDB instead of using relational database.
Are there any typical kinds of applications or domains where the document based database is more suitable than the relational database?
...
Constructor of an abstract class in C#
...lass. That way you can have classes that inherit from that class call the base constructor.
public abstract class A{
private string data;
protected A(string myString){
data = myString;
}
}
public class B : A {
B(string myString) : base(myString){}
}
...
What does it mean that Javascript is a prototype based language?
... the major advantages with Javascript is said to be that it is a prototype based language.
7 Answers
...
How does RewriteBase work in .htaccess
...y own words, after reading the docs and experimenting:
You can use RewriteBase to provide a base for your rewrites. Consider this
# invoke rewrite engine
RewriteEngine On
RewriteBase /~new/
# add trailing slash if missing
rewriteRule ^(([a-z0-9\-]+/)*[a-z0-9\-]+)$ $1/ [NC,R=301,L]
T...
Safely override C++ virtual functions
I have a base class with a virtual function and I want to override that function in a derived class. Is there some way to make the compiler check if the function I declared in the derived class actually overrides a function in the base class? I would like to add some macro or something that ensures ...
In Java, how do I call a base class's method from the overriding method in a derived class?
...
Answer is as follows:
super.Mymethod();
super(); // calls base class Superclass constructor.
super(parameter list); // calls base class parameterized constructor.
super.method(); // calls base class method.
...