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Getting attribute using XPath
...e right way to get it. This is just an assumption where as you have a book table TITLE and PRICE column with populated data. Here's the query
SELECT xpath('/bookstore/book/title/@lang', xmlforest(book.title AS title, book.price AS price), ARRAY[ARRAY[]::TEXT[]]) FROM book LIMIT 1;
...
Is it possible to declare two variables of different types in a for loop?
...and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above will give you:
int i set to 1
double f set to 1.0
std::string s set to "...
What's the point of Spring MVC's DelegatingFilterProxy?
...ent. The positions of the standard filters are fixed (see the filter order table in the >namespace introduction), removing a common source of errors with previous versions of the framework >when users had to configure the filter chain explicitly in theFilterChainProxy bean. You can, of >cou...
Determining 32 vs 64 bit in C++
...esentation. I prefer ENVIRONMENT64 / ENVIRONMENT32. Then I find out what all of the major compilers use for determining if it's a 64 bit environment or not and use that to set my variables.
// Check windows
#if _WIN32 || _WIN64
#if _WIN64
#define ENVIRONMENT64
#else
#define ENVIRONMENT32
#endif...
Load image from url
...into memory twice. Bitmap memory is managed by using a weak reference hash table, so as soon as the image is no longer used by you, it will be garbage collected automatically.
UrlImageViewHelper.setUrlDrawable(imageView, "http://example.com/image.png");
https://github.com/koush/UrlImageViewHelper...
std::function and std::bind: what are they, and when should they be used?
...nd to get g:
auto g = bind(f, _1, 4, _2);
This is more concise than actually writing a functor class to do it.
There are further examples in the article you link to. You generally use it when you need to pass a functor to some algorithm. You have a function or functor that almost does the job yo...
What is the current state of the art in HTML canvas JavaScript libraries and frameworks? [closed]
...s Fabric compare to other Javascript canvas libraries? Here's a comparison table.
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What does if __name__ == “__main__”: do?
...ngs:
it sets a few special variables like __name__, and then
it executes all of the code found in the file.
Let's see how this works and how it relates to your question about the __name__ checks we always see in Python scripts.
Code Sample
Let's use a slightly different code sample to explore ho...
Python time measure function
...e__, (time2-time1)*1000.0))
return ret
return wrap
Note I'm calling f.func_name to get the function name as a string(in Python 2), or f.__name__ in Python 3.
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How do you loop through currently loaded assemblies?
...ughout, but I could not figure out how to effectively show the versions of ALL of the loaded assemblies.
2 Answers
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