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What does new self(); mean in PHP?
...ends MyParentClass {
}
$a = MyChildClass::getInstance();
var_dump($a);
And you'd get this kind of output :
object(MyParentClass)#1 (0) { }
Which means self means MyParentClass -- i.e. here too, the class in which it is written.
With PHP < 5.3, that "the class in which it is written" ...
How do you calculate the average of a set of circular data? [closed]
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Compute unit vectors from the angles and take the angle of their average.
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How to make space between LinearLayout children?
I am programatically adding custom views to a vertical LinearLayout, and I would like there to be some space between the views. I have tried adding: setPadding(0, 1, 0, 1) to my CustomView constructor, but this doesn't seem to have any effect. Any advice?
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How to do an INNER JOIN on multiple columns
I'm working on a homework project and I'm supposed to perform a database query which finds flights either by the city name or the airport code, but the flights table only contains the airport codes so if I want to search by city I have to join on the airports table.
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How should I call 3 functions in order to execute them one after the other?
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In Javascript, there are synchronous and asynchronous functions.
Synchronous Functions
Most functions in Javascript are synchronous. If you were to call several synchronous functions in a row
doSomething();
doSomethingElse();
doSomethingUsefulThisTime();
th...
Some projects cannot be imported because they already exist in the workspace error in Eclipse
I am trying to import a project that me and my co-worker have been working on.. and keep getting this error after I select-- "import" then "import existing project" then click archive file, and then I click next, and this error comes up:
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Passing multiple error classes to ruby's rescue clause in a DRY fashion
...splat operator *.
EXCEPTIONS = [FooException, BarException]
begin
a = rand
if a > 0.5
raise FooException
else
raise BarException
end
rescue *EXCEPTIONS
puts "rescued!"
end
If you are going to use a constant for the array as above (with EXCEPTIONS), note that you cannot defin...
nodeJs callbacks simple example
...have already searched for the same on many websites but not able to understand it properly, Please give me a simple example.
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Get city name using geolocation
I managed to get the user's latitude and longitude using HTML-based geolocation.
11 Answers
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Python nonlocal statement
What does the Python nonlocal statement do (in Python 3.0 and later)?
9 Answers
9
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