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What is the difference between `after_create` and `after_save` and when to use which?
... readers should note that, according to the docs, ActiveRecord's update_all does not invoke any callbacks, including after_*
– user2426679
Jan 10 at 19:34
add a comment
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Timeout on a function call
I'm calling a function in Python which I know may stall and force me to restart the script.
18 Answers
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Gesture recognizer and button actions
...nizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
// Disallow recognition of tap gestures in the segmented control.
if ((touch.view == yourButton)) {//change it to your condition
return NO;
}
return YES;
}
hope it will help
Edit
As Daniel noted you must con...
In Firebase, is there a way to get the number of children of a node without loading all the node dat
...a transaction secure though? It seems it could be easily hacked to artificially increase counts. This could be bad for voting systems.
– Soviut
Apr 7 '14 at 6:10
16
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What character to use to put an item at the end of an alphabetic list?
...ercase "L" and the Greek alphabet sorts after the Latin alphabet on almost all OS's.
– stupidkid
Sep 9 '16 at 2:54
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Given final block not properly padded
...here:
http://www.rsa.com/products/bsafe/documentation/cryptoj35html/doc/dev_guide/group_CJ_SYM__PAD.html
(I assume you have the issue when you try to encrypt)
You can choose your padding schema when you instantiate the Cipher object. Supported values depend on the security provider you are using. ...
How do you increase the max number of concurrent connections in Apache?
...ts 200
MinSpareThreads 25
MaxSpareThreads 75
ThreadsPerChild 25
First of all, whenever an apache is started, it will start 2 child processes which is determined by StartServers parameter. Then each process will start 25 threads determined by ThreadsPerChild parameter so this means 2 process can se...
Join strings with a delimiter only if strings are not null or empty
...
.filter(Boolean) (which is the same as .filter(x => x)) removes all "falsy" values (nulls, undefineds, empty strings etc). If your definition of "empty" is different, then you'll have to provide it, for example:
[...].filter(x => typeof x === 'string' && x.length > 0)
wi...
In c++ what does a tilde “~” before a function name signify?
... memory, etc. etc.
Here's a description from ibm.com:
Destructors are usually used to deallocate memory and do other cleanup for a class object and its class members when the object is destroyed. A destructor is called for a class object when that object passes out of scope or is explicitly delete...
PHP: How to remove all non printable characters in a string?
...to remove other chars...
If you're dealing with Unicode, there are potentially many non-printing elements, but let's consider a simple one: NO-BREAK SPACE (U+00A0)
In a UTF-8 string, this would be encoded as 0xC2A0. You could look for and remove that specific sequence, but with the /u modifier in ...