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Declaring variables inside or outside of a loop

... The scope of local variables should always be the smallest possible. In your example I presume str is not used outside of the while loop, otherwise you would not be asking the question, because declaring it inside the while loop would not be an option, since it would not comp...
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Convert line-endings for whole directory tree (Git)

...should be faster. You don't need the -name *.* either, unless you specifically want only files with a period somewhere in the name. That's a windows glob, not a *nix one. – Useless Aug 15 '11 at 17:31 ...
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What is the id( ) function used for?

... Python objects. Is it the same with memory addresses in C? Conceptually, yes, in that they are both guaranteed to be unique in their universe during their lifetime. And in one particular implementation of Python, it actually is the memory address of the corresponding C object. If yes, wh...
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How do exceptions work (behind the scenes) in c++

... Instead of guessing, I decided to actually look at the generated code with a small piece of C++ code and a somewhat old Linux install. class MyException { public: MyException() { } ~MyException() { } }; void my_throwing_function(bool throwit) { if (...
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String concatenation in Ruby

...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil. When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator. In the end, it is a matter of taste....
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#define macro for debug printing in C?

.... } while (0) idiom ensures that the code acts like a statement (function call). The unconditional use of the code ensures that the compiler always checks that your debug code is valid — but the optimizer will remove the code when DEBUG is 0. If you want to work with #ifdef DEBUG, then change th...
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How to get the result of OnPostExecute() to main activity because AsyncTask is a separate class?

...sk<Void, Void, String> { // you may separate this or combined to caller class. public interface AsyncResponse { void processFinish(String output); } public AsyncResponse delegate = null; public MyAsyncTask(AsyncResponse delegate){ this.delegate = delegate; } ...
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Comparing two NumPy arrays for equality, element-wise

...two NumPy arrays for equality (where equality is defined as: A = B iff for all indices i: A[i] == B[i] )? 6 Answers ...
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unique object identifier in javascript

...niqueId()); Take care to make sure that whatever member you use to internally store the unique ID doesn't collide with another automatically created member name. share | improve this answer ...
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How do you generate dynamic (parameterized) unit tests in python?

... This is called "parametrization". There are several tools that support this approach. E.g.: pytest's decorator parameterized The resulting code looks like this: from parameterized import parameterized class TestSequence(unittes...