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Mutable vs immutable objects
...utable objects gets a lot of bad press (e.g. returning an array of strings from a method) but I'm having trouble understanding what the negative impacts are of this. What are the best practices around using mutable objects? Should you avoid them whenever possible?
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How can I multiply all items in a list together with Python?
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Python 3: use functools.reduce:
>>> from functools import reduce
>>> reduce(lambda x, y: x*y, [1,2,3,4,5,6])
720
Python 2: use reduce:
>>> reduce(lambda x, y: x*y, [1,2,3,4,5,6])
720
For compatible with 2 and 3 use pip install six, then:
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What is the curiously recurring template pattern (CRTP)?
... template assumes that its specialization for any type X will be inherited from singleton<X> and thus will have all its (public, protected) members accessible, including the GetInstance! There are other useful uses of CRTP. For example, if you want to count all instances that currently exist f...
Should accessing SharedPreferences be done off the UI Thread?
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Wow, wasn't expecting to get such a clear answer straight from the source! Thanks much!
– cottonBallPaws
Dec 7 '10 at 1:50
9
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How do I make HttpURLConnection use a proxy?
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This is fairly easy to answer from the internet. Set system properties http.proxyHost and http.proxyPort. You can do this with System.setProperty(), or from the command line with the -D syntax.
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How to redirect output of an already running process [duplicate]
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See Redirecting Output from a Running Process.
Firstly I run the command cat > foo1 in one session and test that data from stdin is copied to the file. Then in another session I redirect the output.
Firstly find the PID of the process:
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List submodules in a Git repository
...les enumerates each submodule path and the URL it refers to.
For example, from root of repository, cat .gitmodules will print contents to the screen (assuming you have cat).
Because .gitmodule files have the Git configuration format, you can use git config to parse those files:
git config --file ...
Best way to get application folder path
...nt.CurrentDirectory
will get you location of where the process got fired from - so for web app running in debug mode from Visual Studio something like "C:\\Program Files (x86)\\IIS Express"
System.IO.Path.GetDirectoryName(
System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase)
w...
What does the `forall` keyword in Haskell/GHC do?
... a -> b.
A confusing point: you may hear that when you omit the forall from a type it is actually still implicitly there. (from Norman's answer: "normally these languages omit the forall from polymorphic types"). This claim is correct, but it refers to the other uses of forall, and not to the Sc...
Visual Studio support for new C / C++ standards?
...n as to why we haven’t implemented C99. It’s really based on interest from our users. Where we’ve received many requests for certain C99 features, we’ve tried to implement them (or analogues). A couple examples are variadic macros, long long, __pragma, __FUNCTION__, and __restrict. If th...