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C++ equivalent of java's instanceof

...ceOfMacros.h #include <set> #include <tuple> #include <typeindex> #define _EMPTY_BASE_TYPE_DECL() using BaseTypes = std::tuple<>; #define _BASE_TYPE_DECL(Class, BaseClass) \ using BaseTypes = decltype(std::tuple_cat(std::tuple<BaseClass>(), Class::BaseTypes())); #de...
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How to reshape data from long to wide format

...ear "value" column. Try dat <- data.frame(id=c(1,1,2,2),blah=c(8,4,7,6),index=c(1,2,1,2)); dcast(dat, id ~ index); cast(dat, id ~ index) and you will not get what you expect. You need to explicitly note the value/value.var - cast(dat, id ~ index, value="blah") and dcast(dat, id ~ index, value.var...
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What does PHP keyword 'var' do?

...tants states that var must not be used, and visibility must be declared on all properties. – Charles Wood Nov 11 '19 at 14:23 ...
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How to make an immutable object in Python?

...ter(1)) p = Point(2, 3) p.x # 2 p.y # 3 Edit: If you want to get rid of indexing either, you can override __getitem__(): class Point(tuple): __slots__ = [] def __new__(cls, x, y): return tuple.__new__(cls, (x, y)) @property def x(self): return tuple.__getitem__(se...
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How to validate an email address using a regular expression?

...he IP address pattern that is floating around the internet with a bug that allows 00 for any of the unsigned byte decimal values in a dot-delimited address, which is illegal. The rest of it appears to be consistent with the RFC 5322 grammar and passes several tests using grep -Po, including cases d...
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Best Practices for Laravel 4 Helpers and Basic Functions?

...lean way: Create a library. That way it'll be autoloaded ONLY when you actually use it. Create a libraries folder inside your app folder Create your library file, create a class in it, and add static functions to it Option 1: Edit start/global.php to add app_path().'/libraries' to the ClassLoader:...
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Can't pickle when using multiprocessing Pool.map()

...f __del__(self): print "... Destructor" def process_obj(self, index): print "object %d" % index return "results" pickle(MethodType, _pickle_method, _unpickle_method) Myclass(nobj=8, workers=3) # problem !!! the destructor is called nobj times (instead of once) Output:...
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What is the best way to profile javascript execution? [closed]

...d your profile block. See the console API here: http://getfirebug.com/wiki/index.php/Console_API Blackbird Blackbird (official site) also has a simpler profiler (can be downloaded from here) share | ...
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Set port for php artisan.php serve

... end up with this for Linux: sudo php artisan serve --port=80 This will allow you to test on localhost without specifying the port in your browser. You can also use this to set up a temporary demo, as I have done. Keep in mind, however, that PHP's built in server is not designed for production. ...
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Find running median from a stream of integers

... elements to all be stored in memory). See below for another answer using indexable skiplists that only requires the most recently seen 100 elements be kept in memory. – Raymond Hettinger May 22 '12 at 5:42 ...