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JavaScript OR (||) variable assignment explanation
... variable is falsy.
The boolean operators in JavaScript can return an operand, and not always a boolean result as in other languages.
The Logical OR operator (||) returns the value of its second operand, if the first one is falsy, otherwise the value of the first operand is returned.
For example:...
Big-O for Eight Year Olds? [duplicate]
I'm asking more about what this means to my code. I understand the concepts mathematically, I just have a hard time wrapping my head around what they mean conceptually. For example, if one were to perform an O(1) operation on a data structure, I understand that the number of operations it has to p...
How to check if a symlink exists
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-L returns true if the "file" exists and is a symbolic link (the linked file may or may not exist). You want -f (returns true if file exists and is a regular file) or maybe just -e (returns true if file exists regardless of type).
According to the GNU manpage, ...
git switch branch without discarding local changes
Alright, lets say one day we make happen to make a bunch of modifications and when we go to commit them we notice we were working on the wrong branch.
...
When would you use a WeakHashMap or a WeakReference?
...mplementation of so I'm trying to figure out what the use case for them is and how the implementation would work. When have you needed to use a WeakHashMap or WeakReference and how was it used?
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What is non-blocking or asynchronous I/O in Node.js?
...rage is a blocking operation as it stalls execution to read. On the other hand, fetch is a non-blocking operation as it does not stall alert(3) from execution.
// Blocking: 1,... 2
alert(1);
var value = localStorage.getItem('foo');
alert(2);
// Non-blocking: 1, 3,... 2
alert(1);
fetch('example.com...
Volatile Vs Atomic [duplicate]
...rite -- such as i++, which is equivalent to i = i + 1, which does one read and one write -- is not atomic, since another thread may write to i between the read and the write.
The Atomic classes, like AtomicInteger and AtomicReference, provide a wider variety of operations atomically, specifically i...
What is the difference between Hibernate and Spring Data JPA
What are the main differences between Hibernate and Spring Data JPA? When should we not use Hibernate or Spring Data JPA? Also, when may Spring JDBC template perform better than Hibernate / Spring Data JPA?
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How do I capture the output into a variable from an external process in PowerShell?
I'd like to run an external process and capture it's command output to a variable in PowerShell. I'm currently using this:
...
How to “test” NoneType in python?
...ariable has None in it or not.
Quoting from is docs,
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object. x is not y yields the inverse truth value.
Since there can be only one instance of None, is would be the preferred way to check...