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Fastest way to check if a string is JSON in PHP?
...any other literal can potentially greatly speed this one up when many of incoming strings are expected to be non-JSON.
– Oleg V. Volkov
Sep 25 '12 at 17:03
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How do I efficiently iterate over each entry in a Java Map?
...ou do that, then it won't work as Entry is a nested Class in Map. java.sun.com/javase/6/docs/api/java/util/Map.html
– ScArcher2
Mar 22 '10 at 13:30
270
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Upgrade python in a virtualenv
...grade the version of python used in a virtualenv (e.g. if a bugfix release comes out)?
12 Answers
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How to print the full traceback without halting the program?
... are automatically reclaimed when garbage collection is enabled and they become unreachable, but it remains more efficient to avoid creating cycles.
On the other hand, by allowing you to access the traceback associated with an exception, Python 3 produce a less surprising result:
import traceb...
Java - get pixel array from image
...sue, the first method is absolutely not the way to go. The getRGB() method combines the alpha, red, green and blue values into one int and then returns the result, which in most cases you'll do the reverse to get these values back.
The second method will return the red, green and blue values direct...
What values should I use for CFBundleVersion and CFBundleShortVersionString?
...r it will get an error when submitting to the App Store. See stackoverflow.com/questions/4933093/….
– Phil
Sep 12 '14 at 21:32
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Calculate business days
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Here's a function from the user comments on the date() function page in the PHP manual. It's an improvement of an earlier function in the comments that adds support for leap years.
Enter the starting and ending dates, along with an array of any holidays th...
What is the point of a private pure virtual function?
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The question in the topic suggest a pretty common confusion. The confusion is common enough, that C++ FAQ advocated against using private virtuals, for a long time, because confusion seemed to be a bad thing.
So to get rid of the confusion first: Yes, private virtual...
Why isn't sizeof for a struct equal to the sum of sizeof of each member?
... state that structure alignment is implementation-defined. Therefore each compiler may choose to align data differently, resulting in different and incompatible data layouts. For this reason, when dealing with libraries that will be used by different compilers, it is important to understand how th...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
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I have had the same problem in two of my programs. My error was this:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
I spent ...