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Is a Java string really immutable?
...
As this topic seems overwhelmingly popular, here's some suggested further reading: Heinz Kabutz's Reflection Madness talk from JavaZone 2009, which covers a lot of the issues in the OP, along with other reflection... well... madness.
It covers why this is sometimes useful. And why, most of the ti...
What is “stdafx.h” used for in Visual Studio?
...instead of starting from scratch, the compiler starts compiling from the already saved results of compiling everything in stdafx.h.
I don't believe that this trick is unique to Microsoft compilers, nor do I think it was an original development.
For Microsoft compilers, the setting that controls th...
Best way to select random rows PostgreSQL
... table and then picks the first 1000 items. Sorting a large table not only reads that table but also involves reading and writing temporary files. The where random() < 0.1 only scans the complete table once.
For large tables this might not what you want as even one complete table scan might take...
Erlang's 99.9999999% (nine nines) reliability
...ong says here:
The AXD301 has achieved a NINE nines reliability (yes, you read that right, 99.9999999%). Let’s put this in context: 5 nines is reckoned to be good (5.2 minutes of downtime/year). 7 nines almost unachievable ... but we did 9.
Why is this? No shared state, plus a sophisticated error...
What is the difference between i++ and ++i?
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The typical answer to this question, unfortunately posted here already, is that one does the increment "before" remaining operations and the other does the increment "after" remaining operations. Though that intuitively gets the idea across, that statement is on the face of it completely w...
load scripts asynchronously
...t('script');
s.type = 'text/javascript';
s.src = src;
s.onload = s.onreadystatechange = function() {
//console.log( this.readyState ); //uncomment this line to see which ready states are called.
if ( !r && (!this.readyState || this.readyState == 'complete') )
{
r = tr...
iPad/iPhone hover problem causes the user to double click a link
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As of jQuery 1.7, .on is preferred to .live. After reading this answer, I found that changing my code to $('a').on('click touchend', function(e) {...}) works superbly.
– Blazemonger
Feb 16 '12 at 16:17
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How is the default submit button on an HTML form determined?
...e submit button is unambiguous but I thought I'd include it for people who read the first part and wonder how to make a submit button successful via JS form submission. Of course, the form's onsubmit handlers will still fire this way whereas they wouldn't via form.submit() so that's another kettle ...
Is Java Regex Thread Safe?
...Pattern) class are immutable and are safe for use by multiple concurrent threads. Instances of the Matcher class are not safe for such use.
If you are looking at performance centric code, attempt to reset the Matcher instance using the reset() method, instead of creating new instances. This would ...
What are metaclasses in Python?
...the object class Foo. If it doesn't, it will use
type to create the class.
Read that several times.
When you do:
class Foo(Bar):
pass
Python does the following:
Is there a __metaclass__ attribute in Foo?
If yes, create in-memory a class object (I said a class object, stay with me here), with th...