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Count character occurrences in a string in C++

... Small note, but the return type is typically signed. For some reason std::count returns type iterator_traits<InputIt>::difference_type, which for most standard containers is std::ptrdiff_t, not std::size_t. ...
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Combining C++ and C - how does #ifdef __cplusplus work?

...f legacy C code. We've started writing in C++, with the intent to eventually convert the legacy code, as well. I'm a little confused about how the C and C++ interact. I understand that by wrapping the C code with extern "C" the C++ compiler will not mangle the C code's names, but I'm no...
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How to make a class property? [duplicate]

...az.bar == 50 assert foo.bar == 50 The setter didn't work at the time we call Bar.bar, because we are calling TypeOfBar.bar.__set__, which is not Bar.bar.__set__. Adding a metaclass definition solves this: class ClassPropertyMetaClass(type): def __setattr__(self, key, value): if key ...
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What does $_ mean in PowerShell?

... This is the variable for the current value in the pipe line, which is called $PSItem in Powershell 3 and newer. 1,2,3 | %{ write-host $_ } or 1,2,3 | %{ write-host $PSItem } For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable ...
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MongoDB: Combine data from multiple collections into one..how?

..., reduce; db.users_comments.remove(); // setup sample data - wouldn't actually use this in production db.users.remove(); db.comments.remove(); db.users.save({firstName:"Rich",lastName:"S",gender:"M",country:"CA",age:"18"}); db.users.save({firstName:"Rob",lastName:"M",gender:"M",country:"US",age:"25...
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Is there a standard way to list names of Python modules in a package?

Is there a straightforward way to list the names of all modules in a package, without using __all__ ? 10 Answers ...
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Calling class staticmethod within the class body?

... def stat_func(): return 42 _ANS = stat_func.__func__() # call the staticmethod def method(self): ret = Klass.stat_func() return ret As an aside, though I suspected that a staticmethod object had some sort of attribute storing the original function, I had no ...
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How to check that an element is in a std::set?

... Note that using count() instead of find() is never better but potentially worse. This is because find() will return after the first match, count() will always iterate over all elements. – Frerich Raabe Nov 9 '09 at 15:50 ...
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What exactly does Perl's “bless” do?

...to a hash (most common case), to an array (not so common), to a scalar (usually this indicates an inside-out object), to a regular expression, subroutine or TYPEGLOB (see the book Object Oriented Perl: A Comprehensive Guide to Concepts and Programming Techniques by Damian Conway for useful examples)...
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How to set versionName in APK filename using gradle?

...ind, but doesn't work well with flavors with different version codes. They all end up with same version code. – weston May 6 '17 at 15:08 2 ...