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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
...votesRef.transaction(function (current_value) {
return (current_value || 0) + 1;
});
For more info, see https://www.firebase.com/docs/transactions.html
UPDATE:
Firebase recently released Cloud Functions. With Cloud Functions, you don't need to create your own Server. You can simply write JavaSc...
Get User's Current Location / Coordinates
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230
To get a user's current location you need to declare:
let locationManager = CLLocationManager()...
setuptools vs. distutils: why is distutils still a thing?
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+50
Have a look at this SO question. It explains all the packaging methods very well, and might help answer your question to some extent: ...
The written versions of the logical operators
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answered Mar 4 '10 at 2:11
GManNickGGManNickG
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Is there a function that returns the current class/method name? [duplicate]
...e.Name;
– James Furey
Oct 17 '12 at 0:44
1
What do to with respect to the "Possible System.NullRe...
What do 'statically linked' and 'dynamically linked' mean?
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450
There are (in most cases, discounting interpreted code) two stages in getting from source code (...
When to use in vs ref vs out
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404
You should use out unless you need ref.
It makes a big difference when the data needs to be ma...
App Inventor 2 低功耗蓝牙 BlueToothLE 拓展 · App Inventor 2 中文网
...件
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最新版拓展下载：
edu.mit.appinventor.ble-20230728.aix
低功耗蓝牙，也称为蓝牙LE 或简称 BLE，是一种类似于经典蓝牙的新通信协议，不同之处在于它旨在消耗更少的功耗和成本，同时保持同等的功能。
因此，低功耗...
How to check if command line tools is installed
I have a macbook pro with OS X 10.8.2.
XCode is installed. I know this as it appears in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is ...
Why does pthread_cond_wait have spurious wakeups?
...ion is given by David R. Butenhof in "Programming with POSIX Threads" (p. 80):
Spurious wakeups may sound strange, but on some multiprocessor systems, making condition wakeup completely predictable might substantially slow all condition variable operations.
In the following comp.programming.th...