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In Firebase, is there a way to get the number of children of a node without loading all the node dat
...way to count children without loading data, but we do plan to add it.
For now, one solution would be to maintain a counter of the number of children and update it every time you add a new child. You could use a transaction to count items, like in this code tracking upvodes:
var upvotesRef = new Fi...
How would you go about parsing Markdown? [closed]
...
The only markdown implementation I know of, that uses an actual parser, is Jon MacFarleane’s peg-markdown. Its parser is based on a Parsing Expression Grammar parser generator called peg.
EDIT: Mauricio Fernandez recently released his Simple Markup Markdown ...
Java equivalent of unsigned long long?
... 64 bit unsigned integer, via unsigned long long int , or via uint64_t . Now, in Java longs are 64 bits, I know. However, they are signed.
...
Long press gesture on UICollectionViewCell
...
it is deprecated methods for now, you can use - (UIContextMenuConfiguration *)collectionView:(UICollectionView *)collectionView contextMenuConfigurationForItemAtIndexPath:(nonnull NSIndexPath *)indexPath point:(CGPoint)point;
– Vikt...
Can I have an IF block in DOS batch file?
In a DOS batch file we can only have 1 line if statement body? I think I found somewhere that I could use () for an if block just like the {} used in C-like programming languages, but it is not executing the statements when I try this. No error message either. This my code:
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How do I add the contents of an iterable to a set?
...er but not both. But in a dynamically typed language where it's sometimes difficult to read the code and know the types of objects flying around, I feel hesitant to use these operators. Someone who doesn't recognize them (or perhaps doesn't even realize that Python allows for operators like these) c...
Hide separator line on one UITableViewCell
...rmally
cell.indentationLevel = 1 // must add this, otherwise default is 0, now actual indentation = indentationWidth * indentationLevel = 10000 * 1 = -10000
and the effect is:
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Difference between addSubview and insertSubview in UIView class
What is the difference between addSubview and insertSubView methods when a view is added programmatically?
4 Answers
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Which is the fastest algorithm to find prime numbers?
...t of primes:
http://www.bigprimes.net/archive/prime/
If you just have to know if a certain number is a prime number, there are various prime tests listed on wikipedia. They are probably the fastest method to determine if large numbers are primes, especially because they can tell you if a number is ...
An example of how to use getopts in bash
... ;;
*)
usage
;;
esac
done
shift $((OPTIND-1))
if [ -z "${s}" ] || [ -z "${p}" ]; then
usage
fi
echo "s = ${s}"
echo "p = ${p}"
Example runs:
$ ./myscript.sh
Usage: ./myscript.sh [-s <45|90>] [-p <string>]
$ ./myscript.sh -h
Usage: ...