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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
...://github.com/firebase/functions-samples/blob/master/child-count/functions/index.js
Update January 2018
The firebase docs have changed so instead of event we now have change and context.
The given example throws an error complaining that event.data is undefined. This pattern seems to work better:...
What's the need of array with zero elements?
...variable-size data member. By declaring it as a 0-length array, it can be indexed just as any other array. You'd then allocate a bts_action struct, of say 1024-byte data size, like so:
size_t size = 1024;
struct bts_action* action = (struct bts_action*)malloc(sizeof(struct bts_action) + size);
...
How to style a checkbox using CSS
...8 and lower versions.
.myCheckbox input {
position: relative;
z-index: -9999;
}
.myCheckbox span {
width: 20px;
height: 20px;
display: block;
background: url("link_to_image");
}
.myCheckbox input:checked + span {
background: url("link_to_another_image");
}
<lab...
Is recursion ever faster than looping?
...med. The more you "IO", the more you have to process. Un-IOing data (aka indexing) is always the biggest performance boost to any system because you don't have to process it in the first place.
– Jeff Fischer
Dec 28 '18 at 19:52
...
Git commits are duplicated in the same branch after doing a rebase
...before rebase. Git default pull configuration is "merge". This is changing indexes of commits performed on the child branch.
The solution: in Git configuration file, configure pull to work in rebase mode:
...
[pull]
rebase = preserve
...
Hope it can help
JN Grx
...
GridLayout and Row/Column Span Woe
...t introducing GridLayout shows this diagram of how spans impact automatic index allocation:
5 Answers
...
Multiprocessing - Pipe vs Queue
...ome shortcuts. For instance, you might have a script that works fine when indexing through a dictionary in under many conditions, but infrequently fails with certain inputs.
Normally we get clues to the failure when the entire python process crashes; however, you don't get unsolicited crash traceb...
How exactly do Django content types work?
...ce usage example. I have 2 suggestions for you:
1: examine this code
def index(request):
media_type='text/html'
if request.META.has_key('CONTENT_TYPE'):
media_type = request.META['CONTENT_TYPE'].split(';')[0]
if media_type.lower() == 'application/json':
return HttpResponse(""...
std::vector versus std::array in C++
... perform a range-checked read with the at() method (you can always use the indexers [] if you don't want this check to be performed).
There are two three main caveats to using std::vector<T>:
You don't have reliable access to the underlying pointer, which may be an issue if you are dealing...
How do I find the duplicates in a list and create another list with them?
...firelynx(a):
vc = pd.Series(a).value_counts()
return vc[vc > 1].index.tolist()
def HenryDev(myList):
newList = set()
for i in myList:
if myList.count(i) >= 2:
newList.add(i)
return list(newList)
def yota(number_lst):
seen_set = set()
duplicat...