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What's the u prefix in a Python string?
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You're right, see 3.1.3. Unicode Strings.
It's been the syntax since Python 2.0.
Python 3 made them redundant, as the default string type is Unicode. Versions 3.0 through 3.2 removed them, but they were re-added in 3.3+ for compatibility with Python 2 to aide the 2...
Java 8 stream's .min() and .max(): why does this compile?
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Let me explain what is happening here, because it isn't obvious!
First, Stream.max() accepts an instance of Comparator so that items in the stream can be compared against each other to find the minimum or maximum, in some optimal order that you don't need to worry too mu...
When to use MongoDB or other document oriented database systems? [closed]
...latform for video- and audio-clips, photos and vector-grafics. We started with MySQL as the database backend and recently included MongoDB for storing all meta-information of the files, because MongoDB better fits the requirements. For example: photos may have Exif information, videos may have a...
How does PHP 'foreach' actually work?
...e prefix this by saying that I know what foreach is, does and how to use it. This question concerns how it works under the bonnet, and I don't want any answers along the lines of "this is how you loop an array with foreach ".
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Use email address as primary key?
... if you simply retrieve a user from the database using the e-mail address. It does matter if you have complex queries with multiple joins.
If you store information about users in multiple tables, the foreign keys to the users table will be the e-mail address. That means that you store the e-mail ad...
What strategies and tools are useful for finding memory leaks in .NET?
... C++ for 10 years. I encountered memory problems, but they could be fixed with a reasonable amount of effort.
15 Answers
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What is the point of noreturn?
...to the calling function after the function finishes (e.g. functions that exit the application, loop forever or throw exceptions as in your example).
This can be used by compilers to make some optimizations and generate better warnings. For example if f has the noreturn attribute, the compiler could...
Why is the Android emulator so slow? How can we speed up the Android emulator? [closed]
...Quick Boot option for Android Emulator. That will save emulator state, and it will start the emulator quickly on the next boot.
Click on Emulator edit button, then click Show Advanced Setting. Then enable Quick Boot like below screenshot.
Android Development Tools (ADT) 9.0.0 (or later) has a fe...
Scanner vs. StringTokenizer vs. String.Split
I just learned about Java's Scanner class and now I'm wondering how it compares/competes with the StringTokenizer and String.Split. I know that the StringTokenizer and String.Split only work on Strings, so why would I want to use the Scanner for a String? Is Scanner just intended to be one-stop-shop...
What's the best visual merge tool for Git? [closed]
What's the best tool for viewing and editing a merge in Git? I'd like to get a 3-way merge view, with "mine", "theirs" and "ancestor" in separate panels, and a fourth "output" panel.
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