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Is there a null-coalescing (Elvis) operator or safe navigation operator in javascript?
...swered Jun 17 '16 at 15:20
James_picJames_pic
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How to initialize a two-dimensional array in Python?
...beginning python and I'm trying to use a two-dimensional list, that I initially fill up with the same variable in every place. I came up with this:
...
What is the difference between “def” and “val” to define a function
...ion every time (new instance of Function1).
def even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = false
val even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = true
With def you can get new function on every call:
val test: () => Int = {
val r = util.Random.nextInt
...
How to execute a MySQL command from a shell script?
... type it in here>
ERROR 1049 (42000): Unknown database 'XXXXXXXX'
Actually, I prefer to store the user and password in ~/.my.cnf so I don't have to put it on the command-line at all:
[client]
user = root
password = XXXXXXXX
Then:
$ mysql -h "server-name" "database-name" < "filename.sql"
...
Generating v5 UUID. What is name and namespace?
...1. Only 128-bits are available and 5 bits are used to specify the type, so all of the hash bits don't make it into the UUID. (Also MD5 is considered cryptographically broken, and SHA1 is on its last legs, so don't use this to verify data that needs to be "very secure"). That said, it gives you a wa...
Delegates in swift?
...interface MyCustomClass: UIViewController <ClassIWantToUseDelegate>, allowing you to init/configure the viewcontroller, as well as call delegate methods on the subviews? Something similar to this?
– Mahmud Ahmad
Aug 11 '16 at 22:32
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Ant task to run an Ant target only if a file exists?
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Check Using Filename filters like DB_*/**/*.sql
Here is a variation to perform an action if one or more files exist corresponding to a wildcard filter. That is, you don't know the exact name of the file.
Here, we are looking for "*.sql" files in any sub-dire...
Python Image Library fails with message “decoder JPEG not available” - PIL
...you are on 64bit or 32bit Ubuntu.
For Ubuntu x64:
sudo ln -s /usr/lib/x86_64-linux-gnu/libjpeg.so /usr/lib
sudo ln -s /usr/lib/x86_64-linux-gnu/libfreetype.so /usr/lib
sudo ln -s /usr/lib/x86_64-linux-gnu/libz.so /usr/lib
Or for Ubuntu 32bit:
sudo ln -s /usr/lib/i386-linux-gnu/libjpeg.so /usr/l...
Application_Error not firing when customerrors = “On”
...the HandleErrorAttribute tells MVC to look for an Error view and it never calls the Application_Error() method. I couldn't find documentation of this but it is explained in this answer on programmers.stackexchange.com.
To get the ApplicationError() method called for every unhandled exception, simpl...
Use didSelectRowAtIndexPath or prepareForSegue method for UITableView?
...() contains the correct value when prepareFroSegue... is called: tableView(_:didSelectrowAtIndexPath:) isn't called until later.
– Nicolas Miari
Jun 7 '16 at 2:21
add a commen...