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Simple Vim commands you wish you'd known earlier [closed]
I'm learning new commands in Vim all the time, but I'm sure everyone learns something new once in a while. I just recently learned about this:
...
Named capturing groups in JavaScript regex?
...e just "syntactic sugar". It helps to use capturing groups only when you really need them and to use non-capturing groups (?:...) in all other circumstances.
The bigger problem (in my opinion) with JavaScript is that it does not support verbose regexes which would make the creation of readable, com...
List comprehension vs map
...ing map() over list comprehension or vice versa? Is either of them generally more efficient or considered generally more pythonic than the other?
...
How do I get bit-by-bit data from an integer value in C?
...ude <stdlib.h>
int *get_bits(int n, int bitswanted){
int *bits = malloc(sizeof(int) * bitswanted);
int k;
for(k=0; k<bitswanted; k++){
int mask = 1 << k;
int masked_n = n & mask;
int thebit = masked_n >> k;
bits[k] = thebit;
}
return bits;
}
in...
Allowed characters in filename [closed]
Where can I find a list of allowed characters in filenames, depending on the operating system?
(e.g. on Linux, the character : is allowed in filenames, but not on Windows)
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What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
...
You usually get this error if your tables use the InnoDB engine. In that case you would have to drop the foreign key, and then do the alter table and drop the column.
But the tricky part is that you can't drop the foreign key using...
FileSystemWatcher Changed event is raised twice
...anner. Because FileSystemWatcher monitors the operating system activities, all events that these applications fire will be picked up.
Now this bit of text is about the Created event, but the same thing applies to other file events as well. In some applications you might be able to get around this ...
BLE协议—广播和扫描 - 创客硬件开发 - 清泛IT社区，为创新赋能！
...广播方式的报文有4种，分别为可连接的非定向广播（ADV_IND）、可连接的定向广播（ADV_DIRECT_IND）、可扫描非定向广播（ADV_SCAN_IND）、不可连接的非定向广播（ADV_NONCONN_IND）
4种广播的使用场景各不相同
可连接的非定向广播（ADV...
@ variables in Ruby on Rails
...cope (current block)
@title is an instance variable - and is available to all methods within the class.
You can read more here:
http://strugglingwithruby.blogspot.dk/2010/03/variables.html
In Ruby on Rails - declaring your variables in your controller as instance variables (@title) makes them ava...
IOException: read failed, socket might closed - Bluetooth on Android 4.3
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I have finally found a workaround. The magic is hidden under the hood of the BluetoothDevice class (see https://github.com/android/platform_frameworks_base/blob/android-4.3_r2/core/java/android/bluetooth/BluetoothDevice.java#L1037).
N...