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How do I “commit” changes in a git submodule? [duplicate]
...t up a git submodule and treated it like a Subversion external - i.e. it's now full of changes that I've just realized haven't been committed or pushed anywhere.
...
Difference between classification and clustering in data mining? [closed]
...neral, in classification you have a set of predefined classes and want to know which class a new object belongs to.
Clustering tries to group a set of objects and find whether there is some relationship between the objects.
In the context of machine learning, classification is supervised learning ...
How to use background thread in swift?
..., after the previous code in outer block")
})
})
Pre Swift 1.2 – Known issue
As of Swift 1.1 Apple didn't support the above syntax without some modifications. Passing QOS_CLASS_BACKGROUND didn't actually work, instead use Int(QOS_CLASS_BACKGROUND.value).
For more information see Apples do...
Why is “throws Exception” necessary when calling a function?
...
In Java, as you may know, exceptions can be categorized into two: One that needs the throws clause or must be handled if you don't specify one and another one that doesn't. Now, see the following figure:
In Java, you can throw anything that ex...
How to check if a Ruby object is a Boolean
...String".boolean?
=> false
>> 1.boolean?
=> false
>> Time.now.boolean?
=> false
>> nil.boolean?
=> false
>> true.boolean?
=> true
>> false.boolean?
=> true
>> (1 ==1).boolean?
=> true
>> (1 ==2).boolean?
=> true
...
Hidden features of Perl?
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There are many non-obvious features in Perl.
For example, did you know that there can be a space after a sigil?
$ perl -wle 'my $x = 3; print $ x'
3
Or that you can give subs numeric names if you use symbolic references?
$ perl -lwe '*4 = sub { print "yes" }; 4->()'
yes
There's a...
How to delay the .keyup() handler until the user stops typing?
I’ve got a search field. Right now it searches for every keyup. So if someone types “Windows”, it will make a search with AJAX for every keyup: “W”, “Wi”, “Win”, “Wind”, “Windo”, “Window”, “Windows”.
...
MySQL: Set user variable from result of query
...ame} and this '{variable_name}', we can replace it with our variable name.
Now, how to assign a value in a variable in mysql. For this we have many ways to do that
Using keyword 'SET'.
Example :-
mysql > SET @a = 1;
Without using keyword 'SET' and using ':='.
Example:-
mysql > @a:=1;
B...
How to take screenshot with Selenium WebDriver
Does anyone know if it's possible to take a screenshot using Selenium WebDriver? (Note: Not Selenium RC)
45 Answers
...
How to run multiple shells on Emacs
I am using Emacs 23.3.1 on windows 7. I know that I can run shell from emacs using M-x shell. I would like to have multiple shell windows in the same time, but typing M-x shell a second time just opens me the same shell window.
...