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Array vs. Object efficiency in JavaScript
...If you need keys (numbers or strings), use an object. If you just need an (ordered) list, use arrays. Period. Performance doesn't enter the discussion. If performance is crucial and you could live with your keys either way, try which one works better for you.
– deceze♦
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What is the difference between a.getClass() and A.class in Java?
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time (getClass()) :23506 ns
time (.class):23838 ns
And switching the order of the calls will even result in getClass() being faster.
import java.util.LinkedHashMap;
public class PerfomanceClass {
public static void main(String[] args) {
long time2 = System.nanoTime();
Class class2 =...
Linux equivalent of the Mac OS X “open” command [closed]
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I made an alias from 'open' to 'xdg-open' in order to have it consistent on both Linux and Mac.
– Adam Byrtek
Oct 20 '09 at 21:19
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Check if a given key already exists in a dictionary and increment it
...ward suggests "the overhead in Exception handling in languages is always a order of magnitude greater than the hash table lookup that determines whether the item exists or not in the dictionary", while you are saying "It also avoids the duplicate key lookup in the dictionary ... if lookup is expensi...
How to append to a file in Node?
...tten by timestamp. You can test with example, set 1000 in place of 100000, order will be random, depends on access to file.
If you want to append to a file, you must use a writable stream like this:
var stream = fs.createWriteStream("append.txt", {flags:'a'});
console.log(new Date().toISOString())...
Why would a static nested interface be used in Java?
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An inner interface has to be static in order to be accessed. The interface isn't associated with instances of the class, but with the class itself, so it would be accessed with Foo.Bar, like so:
public class Baz implements Foo.Bar {
...
}
In most ways, this ...
How do I shutdown, restart, or log off Windows via a bat file?
...ers are also mentioned along with this one. Here they are in no particular order.
The -f option from JosephStyons
Using rundll32 from VonC
The Run box from Dean
Remote shutdown from Kip
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Easy way to concatenate two byte arrays
...go back and edit the line where you create the result byte array. Also, re-ordering the arrays is simple, unlike using the arraycopy method.
– Wayne Uroda
Aug 27 '12 at 11:38
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Can I install Python 3.x and 2.x on the same Windows computer?
...ndows) which is then associated with py and pyw scripts, respectively.
In order to use the new launcher (without manually setting up your own associations to it), leave the "Register Extensions" option enabled. I'm not quite sure why, but on my machine it left Py 2.7 as the "default" (of the launc...
Check if a program exists from a Makefile
... PATH")))
Note the use of the := assignment operator that is required in order to force immediate evaluation of the RHS expression. If your Makefile changes the PATH, then instead of the last line above you will need:
$(if $(shell PATH=$(PATH) which $(exec)),some string,$(error "No $(exec...