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Why is string concatenation faster than array join?
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Browser string optimizations have changed the string concatenation picture.
Firefox wa...
psql: FATAL: Peer authentication failed for user “dev”
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Difference between volatile and synchronized in Java
...ht require locks, though not on modern 64 bit hardware. Under the new (JSR-133) memory model for Java 5+, the semantics of volatile have been strengthened to be almost as strong as synchronized with respect to memory visibility and instruction ordering (see http://www.cs.umd.edu/users/pugh/java/memo...
not None test in Python [duplicate]
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if val is not None:
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is the Pythonic idiom for testing that a variable is not set ...
Using Gradle to build a jar with dependencies
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Python: Making a beep noise
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On Windows, if you want to just make the computer make a beep sound:
import winsound
frequenc...
What is ASP.NET Identity's IUserSecurityStampStore interface?
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edited Jan 24 '17 at 14:41
niico
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What does the @ symbol represent in objective-c?
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The @ character isn't used in C or C++ identifiers, so it's used to introduce Objective-C lang...
std::back_inserter for a std::set?
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set doesn't have push_back because the position of an element is determined by the comparator ...
What does the arrow operator, '->', do in Java?
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That's part of the syntax of the new lambda expressions, to be introduced in Java 8. There are...