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How can I select an element with multiple classes in jQuery?
... What is the difference between this answer and the accepted one?
– Vivian River
Aug 9 '11 at 14:32
49
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JComboBox Selection Change Listener?
...ctionListener (new ActionListener () {
public void actionPerformed(ActionEvent e) {
doSomething();
}
});
@John Calsbeek rightly points out that addItemListener() will work, too. You may get 2 ItemEvents, though, one for the deselection of the previously selected item, and another ...
What's the difference between using “let” and “var”?
...ord was introduced to the language was function scope is confusing and was one of the main sources of bugs in JavaScript.
Take a look at this example from another stackoverflow question:
var funcs = [];
// let's create 3 functions
for (var i = 0; i < 3; i++) {
// and store them in funcs
fun...
Understanding the transclude option of directive definition?
I think this is one of the hardest concept for me to understand with angularjs's directive.
6 Answers
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How to determine the memory footprint (size) of a variable?
...filer
https://github.com/arnaud-lb/php-memory-profiler. This is what I've done on my Ubuntu server to enable it:
sudo apt-get install libjudy-dev libjudydebian1
sudo pecl install memprof
echo "extension=memprof.so" > /etc/php5/mods-available/memprof.ini
sudo php5enmod memprof
service apache2 rest...
PHP: merge two arrays while keeping keys instead of reindexing?
How can I merge two arrays (one with string => value pairs and another with int => value pairs) while keeping the string/int keys? None of them will ever overlap (because one has only strings and the other has only integers).
...
How do I make Git treat a file as binary?
...
@neves : you got to make one, either locally in your repo or globally as e.g. ~/.gitattributes and then running git config --global core.attributesfile ~/.gitattributes see stackoverflow.com/questions/28026767/…
– jan-glx
...
GB English, or US English?
...tend to do the same, but being careful of what Chris mentions - if you use one spelling in the API you should probably use the same one elsewhere in the project.
– Mark Baker
Oct 1 '08 at 14:55
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How can I delete all Git branches which have been merged?
...n merged? Is there an easy way to delete them all instead of deleting them one by one?
45 Answers
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Validate uniqueness of multiple columns
...
You can use validates to validate uniqueness on one column:
validates :user_id, uniqueness: {scope: :friend_id}
The syntax for the validation on multiple columns is similar, but you should provide an array of fields instead:
validates :attr, uniqueness: {scope: [:attr1...