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Using str_replace so that it only acts on the first match?
... Another downside is you have to use preg_quote() on the "needle" and escape meta-characters $ and \ in the replacement.
– Josh Davis
Aug 10 '09 at 2:53
32
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What is an initialization block?
... are two types of initialization blocks:
instance initialization blocks, and
static initialization blocks.
This code should illustrate the use of them and in which order they are executed:
public class Test {
static int staticVariable;
int nonStaticVariable;
// Static init...
What does the Q_OBJECT macro do? Why do all Qt objects need this macro?
I just started using Qt and noticed that all the example class definitions have the macro Q_OBJECT as the first line. What is the purpose of this preprocessor macro?
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How to Store Historical Data
Some co-workers and I got into a debate on the best way to store historical data. Currently, for some systems, I use a separate table to store historical data, and I keep an original table for the current, active record. So, let's say I have table FOO. Under my system, all active records will go ...
Difference between and ?
Every time I have to add a handler or module for ASP.NET with IIS7, the instructions always tell me to incorporate it into two sections: system.web and system.webserver .
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How does variable assignment work in JavaScript?
...perty of an existing object. In the second example, you are assigning a brand new object.
a = b = {};
a and b are now pointers to the same object. So when you do:
a.foo = 'bar';
It sets b.foo as well since a and b point to the same object.
However!
If you do this instead:
a = 'bar';
you...
How do I use the ternary operator ( ? : ) in PHP as a shorthand for “if / else”?
Based on the examples from this page , I have the working and non-working code samples below.
14 Answers
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Infinite scrolling with React JS
... infinite scrolling with React. I have come across react-infinite-scroll and found it inefficient as it just adds nodes to the DOM and doesn't remove them. Is there any proven solution with React which will add, remove and maintains constant number of nodes in the DOM.
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Python: most idiomatic way to convert None to empty string?
... keeping the else, but thanks for the str(s) tip so multiple types can be handled. nice!
– Mark Harrison
Jul 1 '09 at 9:39
13
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How to develop and test an app that sends emails (without filling someone's mailbox with test data)?
...d email. Sometimes it's one or two messages at a time. Sometimes it's thousands of messages.
9 Answers
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