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class
...t; self opens up self's singleton class, so that methods can be redefined for the current self object (which inside a class or module body is the class or module itself). Usually, this is used to define class/module ("static") methods:
class String
class << self
def value_of obj
o...
Is there a performance difference between i++ and ++i in C?
Is there a performance difference between i++ and ++i if the resulting value is not used?
14 Answers
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How can I add a class attribute to an HTML element generated by MVC's HTML Helpers?
ASP.NET MVC can generate HTML elements using HTML Helpers, for example @Html.ActionLink() , @Html.BeginForm() and so on.
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How to read environment variables in Scala
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Since Scala 2.9 you can use sys.env for the same effect:
scala> sys.env("HOME")
res0: String = /home/paradigmatic
I think is nice to use the Scala API instead of Java. There are currently several project to compile Scala to other platforms than JVM (.NET, ...
How often to commit changes to source control? [closed]
...ten should I commit changes to source control ? After every small feature, or only for large features ?
26 Answers
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Reading a delimited string into an array in Bash
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In order to convert a string into an array, please use
arr=($line)
or
read -a arr <<< $line
It is crucial not to use quotes since this does the trick.
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Combine two columns of text in pandas dataframe
...tenate them directly:
df["period"] = df["Year"] + df["quarter"]
If one (or both) of the columns are not string typed, you should convert it (them) first,
df["period"] = df["Year"].astype(str) + df["quarter"]
Beware of NaNs when doing this!
If you need to join multiple string columns, you ca...
What is NSLayoutConstraint “UIView-Encapsulated-Layout-Height” and how should I go about forcing it
...g under iOS 8 and I'm using automatic cell heights from constraints in a storyboard.
17 Answers
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How do I get the path of the Python script I am running in? [duplicate]
...ou the path of the current file, resolving any symlinks in the path. This works fine on my mac.
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Which concurrent Queue implementation should I use in Java?
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Basically the difference between them are performance characteristics and blocking behavior.
Taking the easiest first, ArrayBlockingQueue is a queue of a fixed size. So if you set the size at 10, and attempt to insert an 11th element, the insert statement will block unt...