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Case objects vs Enumerations in Scala
...es. However, I find in general that enumerations are a bit clumsy in Scala and have the feel of an awkward add-on, so I now tend to use case objects. A case object is more flexible than an enum:
sealed trait Currency { def name: String }
case object EUR extends Currency { val name = "EUR" } //etc.
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What exactly are “spin-locks”?
...ritical sections etc), operating system puts your thread in the WAIT state and preempts it by scheduling other threads on the same core. This has a performance penalty if the wait time is really short, because your thread now has to wait for a preemption to receive CPU time again.
Besides, kernel ob...
What key shortcuts are to comment and uncomment code?
There were Ctrl + E + C (comment) and Ctrl + E + U (uncomment) in older versions, or Ctrl + K + C and Ctrl + K + U .
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How can I know which parts in the code are never used?
..., it's much more difficult. Statically it requires whole program analysis, and even though link time optimization may actually remove dead code, in practice the program has been so much transformed at the time it is performed that it is near impossible to convey meaningful information to the user.
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SQL query return data from multiple tables
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Part 1 - Joins and Unions
This answer covers:
Part 1
Joining two or more tables using an inner join (See the wikipedia entry for additional info)
How to use a union query
Left and Right Outer Joins (this stackOverflow answer is excelle...
Auto Scale TextView Text to Fit within Bounds
...ize wrapping text in a TextView so that it will fit within its getHeight and getWidth bounds. I'm not simply looking for a way to wrap the text- I want to make sure it both wraps and is small enough to fit entirely on the screen.
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Class does not implement its superclass's required members
So I updated to Xcode 6 beta 5 today and noticed I received errors in nearly all of my subclasses of Apple's classes.
4 Ans...
RESTful Services - WSDL Equivalent
I have been reading about REST and SOAP, and understand why implementing REST can be beneficial over using a SOAP protocol. However, I still don't understand why there isn't the "WSDL" equivalent in the REST world. I have seen posts saying there is "no need" for the WSDL or that it would be redund...
Storing Images in PostgreSQL
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Updating to 2012, when we see that image sizes, and number of images, are growing and growing, in all applications...
We need some distinction between "original image" and "processed image", like thumbnail.
As Jcoby's answer says, there are two options, then, I recommend:
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What is the difference between sql and mysql [closed]
I am new to databases and I was wondering: What is the difference between SQL and MySQL ?
5 Answers
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