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Differences between fork and exec
...d process (parent) as its parent PID (PPID). Because the two processes are now running exactly the same code, they can tell which is which by the return code of fork - the child gets 0, the parent gets the PID of the child. This is all, of course, assuming the fork call works - if not, no child is c...
When do we have to use copy constructors?
I know that C++ compiler creates a copy constructor for a class. In which case do we have to write a user-defined copy constructor? Can you give some examples?
...
Ternary operator is twice as slow as an if-else block?
...
RunIfElse(array, 1);
RunConditional(array, 1);
// Now really time it
RunIfElse(array, 1000);
RunConditional(array, 1000);
}
static void RunIfElse(int[] array, int iterations)
{
long value = 0;
Stopwatch sw = Stopwatch.Star...
How to thoroughly purge and reinstall postgresql on ubuntu? [closed]
...ake sure PostgreSQL isn't running. ps -C postgres should show no results.
Now run:
apt-get --purge remove postgresql\*
to remove everything PostgreSQL from your system. Just purging the postgres package isn't enough since it's just an empty meta-package.
Once all PostgreSQL packages have been r...
How to convert a DOM node list to an array in Javascript?
...obj[i];
}
return array;
}
UPDATE:
As other answers suggest, you can now can use in modern environments the spread syntax or the Array.from method:
const array = [ ...nodeList ] // or Array.from(nodeList)
But thinking about it, I guess the most common use case to convert a NodeList to an Ar...
How to change the href for a hyperlink using jQuery
...ery 1.4, the last example doesn't require using each - the following would now be possible: $(selector).attr('href', function() { return this.replace(/.../, '...'); });
– David Hedlund
Aug 11 '10 at 14:17
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Explanation of [].slice.call in javascript?
...ray, then iterate through the object it's running on (originally an array, now a NodeList) and keep appending the elements of that object to the empty array it created, which is eventually returned. Here's an article on this.
EDIT:
So it starts with an empty array [], then slice is used to
co...
Simple explanation of MapReduce?
...rite it like this
A = [7, 8, 9]
sum = A.reduce( 0, (x, y) => x + y )
Now it's a little confusing why there are 2 arguments (0 and the function with x and y) passed. For a reduce function to be useful, it must be able to take 2 items, compute something and "reduce" that 2 items to just one sing...
Why doesn't Ruby support i++ or i-- (increment/decrement operators)?
...
One reason is that up to now every assignment operator (i.e. an operator which changes a variable) has a = in it. If you add ++ and --, that's no longer the case.
Another reason is that the behavior of ++ and -- often confuse people. Case in point: ...
Difference between “git add -A” and “git add .”
... -A ..
git add <path> is the same as "git add -A <path>" now, so that
"git add dir/" will notice paths you removed from the directory and
record the removal.
In older versions of Git, "git add <path>" ignored removals.
You can say "git add --ignore-removal <pa...