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PHP Fatal error: Cannot redeclare class
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It means you've already created a class.
For instance:
class Foo {}
// some code here
class Foo {}
That second Foo would throw the error.
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How do I create and read a value from cookie?
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Here are functions you can use for creating and retrieving cookies.
function createCookie(name, value, days) {
var expires;
if (days) {
var date = new Date();
date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
expi...
Understanding reference counting with Cocoa and Objective-C
...C and Cocoa with a view to playing with the iPhone SDK. I'm reasonably comfortable with C's malloc and free concept, but Cocoa's references counting scheme has me rather confused. I'm told it's very elegant once you understand it, but I'm just not over the hump yet.
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Objective-C ARC: strong vs retain and weak vs assign
There are two new memory management attributes for properties introduced by ARC, strong and weak .
8 Answers
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Fast check for NaN in NumPy
I'm looking for the fastest way to check for the occurrence of NaN ( np.nan ) in a NumPy array X . np.isnan(X) is out of the question, since it builds a boolean array of shape X.shape , which is potentially gigantic.
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How to set date format in HTML date input tag?
I am wondering whether it is possible to set the date format in the html <input type="date"></input> tag... Currently it is yyyy-mm-dd, while I need it in the dd-mm-yyyy format.
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What does “export” do in shell programming? [duplicate]
As far as I can tell, variable assignment is the same whether it is or is not preceded by "export". What's it for?
3 Answer...
Create a new Ruby on Rails application using MySQL instead of SQLite
...base.yml file to mysql and make sure you specify a valid username and password, and optionally, a socket:
development:
adapter: mysql2
database: db_name_dev
username: koploper
password:
host: localhost
socket: /tmp/mysql.sock
Next, make sure you edit your Gemfile to include the mysql2...
What does `someObject.new` do in Java?
...ic inner class from outside the containing class body, as described in the Oracle docs.
Every inner class instance is associated with an instance of its containing class. When you new an inner class from within its containing class it uses the this instance of the container by default:
public cla...
转：postfix安装Q&A - 更多技术 - 清泛网 - 专注C/C++及内核技术
...ngda老大的资料安装成功postfix（地址在这里http://www.extmail.org/forum/archive/2/0510/563.html）。现在把我安装过程中遇到的问题及解决方法提供给大家，以方便新手。高手就不要看了
说明一下：Q代表安装过程中遇到的问题，或者是...