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Can you explain the concept of streams?
I understand that a stream is a representation of a sequence of bytes. Each stream provides means for reading and writing bytes to its given backing store. But what is the point of the stream? Why isn't the backing store itself what we interact with?
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Most efficient way to determine if a Lua table is empty (contains no entries)?
What's the most efficient way to determine if a table is empty (that is, currently contains neither array-style values nor dict-style values)?
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What is the “volatile” keyword used for?
...of the scope of the program itself. The compiler will then avoid any optimisations that may result in problems if the variable changes "outside of its control".
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Is there any reason to use a synchronous XMLHttpRequest?
...synchronous requests with XMLHttpRequest but obviously the fact that there is the ability to do synchronous requests indicates there might be a valid reason to do so. So what might that valid reason be?
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Why create “Implicitly Unwrapped Optionals”, since that implies you know there's a value?
...unwrapped then why create an optional in the first place?
For example, why is this:
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Is null check needed before calling instanceof?
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No, a null check is not needed before using instanceof.
The expression x instanceof SomeClass is false if x is null.
From the Java Language Specification, section 15.20.2, "Type comparison operator instanceof":
"At run time, the resul...
jQuery hasAttr checking to see if there is an attribute on an element [duplicate]
How do you check if there is an attribute on an element in jQuery? Similar to hasClass , but with attr ?
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What is an AngularJS directive?
... AngularJS documentation and several tutorials, and I have been quite surprised at how unapproachable the documentation is.
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SQL left join vs multiple tables on FROM line?
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The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use both INNER ...
Why should C++ programmers minimize use of 'new'?
...n Stack Overflow question Memory leak with std::string when using std::list<std::string> , and one of the comments says this:
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