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Is there a “null coalescing” operator in JavaScript?
...an results in false, the assignment will use the second operand. Beware of all the cases below:
alert(Boolean(null)); // false
alert(Boolean(undefined)); // false
alert(Boolean(0)); // false
alert(Boolean("")); // false
alert(Boolean("false")); // true -- gotcha! :)
This means:
var whatIWant = n...
How do I immediately execute an anonymous function in PHP?
In JavaScript, you can define anonymous functions that are executed immediately:
9 Answers
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Reusing output from last command in Bash
...ng backticks: `your_cmd` According to the Gnu Bash manual they are functionally identical. Of course this is also subject to the warning raised by @memecs
– user2065875
Apr 20 '15 at 21:33
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What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
...ceeds the size of the stack, and it has to be re-created. So there can actually, depending on the use case, be a performance increase when using new Array() because you can prevent the overflow from happening.
As pointed out in this answer, new Array(5) will not actually add five undefined items to...
How to use putExtra() and getExtra() for string data
...an someone please tell me how exactly to use getExtra() and putExtra() for intents? Actually I have a string variable, say str, which stores some string data. Now, I want to send this data from one activity to another activity.
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How to iterate over rows in a DataFrame in Pandas
... From the documentation: "Iterating through pandas objects is generally slow. In many cases, iterating manually over the rows is not needed[...]". Your answer is correct (in the context of the question) but does not mention this anywhere, so it isn't a very good one.
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How do I check CPU and Memory Usage in Java?
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If you are looking specifically for memory in JVM:
Runtime runtime = Runtime.getRuntime();
NumberFormat format = NumberFormat.getInstance();
StringBuilder sb = new StringBuilder();
long maxMemory = runtime.maxMemory();
long allocatedMemory = runtime...
Measuring text height to be drawn on Canvas ( Android )
... approximate height. I've also been messing around with FontMetrics , but all these seem like approximate methods that suck.
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Why main does not return 0 here?
I was just reading
3 Answers
3
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Permission denied on accessing host directory in Docker
In short: I am trying to mount a host directory in Docker, but then I can not access it from within the container, even if the access permissions look good.
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