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Java String split removed empty values
...le more details:
split(regex) internally returns result of split(regex, 0) and in documentation of this method you can find (emphasis mine)
The limit parameter controls the number of times the pattern is applied and therefore affects the length of the resulting array.
If the limit n is greater than...
Image Greyscale with CSS & re-color on mouse-over?
I am looking to take an icon that is colored (and will be a link) and turn it greyscale until the user places their mouse over the icon (where it would then color the image).
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How can I change image tintColor in iOS and WatchKit
...mage.
You must add your image to an Asset Catalog in your WatchKit App, and set the image set to be rendered as a Template Image in the Attributes Inspector. Unlike for an iPhone app, you cannot set the template rendering in code in the WatchKit Extension at present.
Set that image to be used in ...
RESTful Authentication
What does RESTful Authentication mean and how does it work? I can't find a good overview on Google. My only understanding is that you pass the session key (remeberal) in the URL, but this could be horribly wrong.
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How do I retrieve the number of columns in a Pandas data frame?
How do you programmatically retrieve the number of columns in a pandas dataframe? I was hoping for something like:
6 Answer...
Overriding fields or properties in subclasses
I have an abstract base class and I want to declare a field or a property that will have a different value in each class that inherits from this parent class.
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How do I break out of a loop in Scala?
...> sum+=i)
(warning--this depends on details of how the takeWhile test and the foreach are interleaved during evaluation, and probably shouldn't be used in practice!).
(1b) Use tail recursion instead of a for loop, taking advantage of how easy it is to write a new method in Scala:
var sum = 0
...
What is a sealed trait?
...only extended in a single file, the compiler knows every possible subtypes and can reason about it.
For instance with the declaration:
sealed trait Answer
case object Yes extends Answer
case object No extends Answer
The compiler will emit a warning if a match is not exhaustive:
scala> val x:...
Embedded MongoDB when running integration tests
... the accepted answer from @rozky (a lot has been changed in both the Mongo and Embedded MongoDB libraries).
package com.example.mongo;
import com.mongodb.BasicDBObject;
import com.mongodb.MongoClient;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import de.fla...
What's the result of += in C and C++?
...
Semantics of the compound assignment operators is different in C and C++:
C99 standard, 6.5.16, part 3:
An assignment operator stores a value in the object designated by the left operand. An
assignment expression has the value of the left operand after the assignment, but is not an
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