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Standard alternative to GCC's ##__VA_ARGS__ trick?

... It is possible to avoid the use of GCC's ,##__VA_ARGS__ extension if you are willing to accept some hardcoded upper limit on the number of arguments you can pass to your variadic macro, as described in Richard Hansen's answer to this question. If you do not want to hav...
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Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable

...uld be noticeable impact. Enumerable.Empty does not create an object per call thus putting less load on GC. If the code is in low-throughput location, then it boils down to aesthetic considerations though. share |...
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WebService Client Generation Error with JDK8

.../jre/lib and then write this line in it: javax.xml.accessExternalSchema = all That's all. Enjoy JDK 8. share | improve this answer | follow | ...
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How does the @property decorator work in Python?

...is just syntactic sugar; the syntax: @property def foo(self): return self._foo really means the same thing as def foo(self): return self._foo foo = property(foo) so foo the function is replaced by property(foo), which we saw above is a special object. Then when you use @foo.setter(), what you ...
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Python __call__ special method practical example

I know that __call__ method in a class is triggered when the instance of a class is called. However, I have no idea when I can use this special method, because one can simply create a new method and perform the same operation done in __call__ method and instead of calling the instance, you can c...
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Selecting multiple columns in a pandas dataframe

...). df1 = df[['a', 'b']] Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead: df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
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Ruby on Rails: Delete multiple hash keys

...re unaware of the Hash#except method ActiveSupport adds to Hash. It would allow your code to be simplified to: redirect_to my_path(params.except(:controller, :action, :other_key)) Also, you wouldn't have to monkey patch, since the Rails team did it for you! ...
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How to create NS_OPTIONS-style bitmask enumerations in Swift?

...tains(.secondOption) { print("multipleOptions has SecondOption") } let allOptions = MyOptions(rawValue: 7) if allOptions.contains(.thirdOption) { print("allOptions has ThirdOption") } Swift 2.0 In Swift 2.0, protocol extensions take care of most of the boilerplate for these, which are now...
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How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?

Is there a way to call a block with a primitive parameter after a delay, like using performSelector:withObject:afterDelay: but with an argument like int / double / float ? ...
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Insert picture into Excel cell [closed]

... appear on hover over. Microsoft Office 365 (2019) introduced new things called comments and renamed the old comments as "notes". Therefore in the steps above do New Note instead of Insert Comment. All other steps remain the same and the functionality still exists. There is also a $20 product fo...