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What does the caret operator (^) in Python do?
...his way:
1000 # 8 (binary)
0011 # 3 (binary)
---- # APPLY XOR ('vertically')
1011 # result = 11 (binary)
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Bash, no-arguments warning, and case decisions
... You mean the errors coming out of a particular program you're calling? You can put > /dev/null and/or 2> /dev/null after that to send its standard output and/or standard error streams into oblivion.
– Thomas
Mar 11 '10 at 20:14
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What are the GCC default include directories?
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There is a command with a shorter output, which allows to automatically cut the include pathes from lines, starting with a single space:
$ echo | gcc -Wp,-v -x c++ - -fsyntax-only
ignoring nonexistent directory "/usr/lib/gcc/x86_64-redhat-linux/4.8.2/include-fixed"
ignori...
Returning JSON from PHP to JavaScript?
I have a PHP script that's being called through jQuery AJAX. I want the PHP script to return the data in JSON format to the javascript. Here's the pseudo code in the PHP script:
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Scrollview vertical and horizontal in android
I'm really tired looking for a solution for vertical and horizontal Scrollview.
11 Answers
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How to stop a JavaScript for loop?
...try.size === remData.size;
});
Array#findIndex stops the first time the callback returns a truthy value, returning the index for that call to the callback; it returns -1 if the callback never returns a truthy value. Array#find also stops when it finds what you're looking for, but it returns the en...
Why does google.load cause my page to go blank?
...e_thread/thread/e07c2606498094e6
Using one of the ideas, you could use a callback for the load to force it use append rather than doc.write:
setTimeout(function(){google.load('visualization', '1', {'callback':'alert("2 sec wait")', 'packages':['corechart']})}, 2000);
This demonstrates the 2 seco...
What is a “first chance exception”?
...ception? How and where does it originate in a .NET program? And why is it called by that peculiar name (what 'chance' are we talking about)?
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Proper use of beginBackgroundTaskWithExpirationHandler
...l need to wrap it in a background task. It's also very important that you call endBackgroundTask when you're finished - otherwise the app will be killed after its allotted time has expired.
Mine tend look something like this:
- (void) doUpdate
{
dispatch_async(dispatch_get_global_queue(DISPAT...
Event system in Python
...r methods', which is a
simple implementation of the Observer pattern.
Basically, the handler methods (callables) are stored in an array and are each called when the event 'fires'.
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The disadvantage of Observer event systems is that you can only register the handlers on the actual Ev...