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What is “android:allowBackup”?
...e, either open the lint warnings view, where you can select the lint error and see a longer explanation, or invoke the quick fix (Ctrl-1) on the error line, and one of the suggestions is "Explain this issue", which will also pop up a fuller explanation. If you are not using Eclipse, you can generate...
What does !! mean in ruby?
...ly not necessary to use though since the only false values to Ruby are nil and false, so it's usually best to let that convention stand.
Think of it as
!(!some_val)
One thing that is it used for legitimately is preventing a huge chunk of data from being returned. For example you probably don't ...
Why does find -exec mv {} ./target/ + not work?
I want to know exactly what {} \; and {} \+ and | xargs ... do. Please clarify these with explanations.
5 Answers
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How to count certain elements in array?
... to use the right tool for the job" -requests never made much sense to me. And we can argue what is most elegant. E.g. for me, making a function call per element to just to compare it to a value is not elegant.
– Felix Kling
May 25 '11 at 8:33
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Difference between SRC and HREF
The SRC and HREF attributes are used to include some external entities like an image, a CSS file, a HTML file, any other web page or a JavaScript file.
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What is the rationale for all comparisons returning false for IEEE754 NaN values?
...ify things a bit.
First off, floating-point numbers are not real numbers, and floating-point arithmetic does not satisfy the axioms of real arithmetic. Trichotomy is not the only property of real arithmetic that does not hold for floats, nor even the most important. For example:
Addition is not...
Best Practice for Forcing Garbage Collection in C#
...need them. If you have custom objects, look at using the "using statement" and the IDisposable interface.
This link has some good practical advice with regards to freeing up memory / garbage collection etc:
http://msdn.microsoft.com/en-us/library/66x5fx1b.aspx
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Why switch is faster than if
...ave a check, a jump to the next clause, a check, a jump to the next clause and so on. With switch the JVM loads the value to compare and iterates through the value table to find a match, which is faster in most cases.
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Swift equivalent for MIN and MAX macros
In C / Objective-C it is possible to find the minimum and maximum value between two numbers using MIN and MAX macros. Swift doesn't support macros and it seems that there are no equivalents in the language / base library. Should one go with a custom solution, maybe based on generics like this one ?...
How to mount a host directory in a Docker container
...ou can do this. The simplest way to do so is to use the dockerfile ADD command like so:
ADD . /path/inside/docker/container
However, any changes made to this directory on the host after building the dockerfile will not show up in the container. This is because when building a container, docker co...