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Deep null checking, is there a better way?

...'d say cake?.frosting?.berries?.loader and the compiler would generate all the short-circuiting checks for you. It didn't make the bar for C# 4. Perhaps for a hypothetical future version of the language. Update (2014): The ?. operator is now planned for the next Roslyn compiler release. Note ...
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Matching a space in regex

...X is the physical tab character (and each is preceded by a single space in all those examples). These will work in every* regex engine I've ever seen (some of which don't even have the one-or-more "+" character, ugh). If you know you'll be using one of the more modern regex engines, "\s" and its v...
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Can you split a stream into two streams?

... @JoD It is thread-safe if heads and tails are thread-safe. Additionally, assuming the use of non-parallel streams, only the order is not guaranteed, so they are thread-safe. It's up to the programmer to fix concurrency issues, so this answer is perfectly suitable if the collections are threa...
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What does the “map” method do in Ruby?

... Ahhh I get it. So .map actually mutates the array while .each just loops through the array to access the values while leaving the original array untouched? – bigpotato Aug 23 '12 at 4:18 ...
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Targeting .NET Framework 4.5 via Visual Studio 2010

Today I installed the .NET Framework 4.5 on my machine expecting to be able to use it from Visual Studio 2010, since it's just a minor update that should't pose problems for Visual Studio 2010. Unfortunately I am not, even manually removing certain 4.0 and adding the corresponding 4.5 assemblies r...
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How to convert an array of strings to an array of floats in numpy?

...(or equivalently, use a list comprehension). (In Python 3, you'll need to call list on the map return value if you use map, since map returns an iterator now.) However, if it's already a numpy array of strings, there's a better way. Use astype(). import numpy as np x = np.array(['1.1', '2.2', '3....
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Convert light frequency to RGB?

...teachers may have told us (well mine did). Too bad, but in practice not usually fatal. – Francis Davey May 29 '10 at 22:58 1 ...
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Reduce, fold or scan (Left/Right)?

... In general, all 6 fold functions apply a binary operator to each element of a collection. The result of each step is passed on to the next step (as input to one of the binary operator's two arguments). This way we can cumulate a result. ...
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Converting from longitude\latitude to Cartesian coordinates

...'re talking about a distance of a few feet and even then there is theoretically curvature of the Earth... If you require more rigidly WGS-84 compatible approach checkout the "Vincenty Formula." I understand where starblue is coming from, but good software engineering is often about trade offs, so ...
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pass post data with window.location.href

...n attribute of the form to the URL and the method attribute to POST, then call the submit method on the form tag. share | improve this answer | follow | ...