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What does __FILE__ mean in Ruby?
I see this all the time in Ruby:
4 Answers
4
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Using generic std::function objects with member functions in one class
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A non-static member function must be called with an object. That is, it always implicitly passes "this" pointer as its argument.
Because your std::function signature specifies that your function doesn't take any arguments (<void(void)>), you must bind the ...
How to make MySQL handle UTF-8 properly
... My understanding is that utf8 within MySQL only refers to a small subset of full Unicode. You should use utf8mb4 instead to force full support. See mathiasbynens.be/notes/mysql-utf8mb4 "For a long time, I was using MySQL’s utf8 charset for databases, tables, and columns, assuming i...
How to check if all elements of a list matches a condition?
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The best answer here is to use all(), which is the builtin for this situation. We combine this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
>>...
Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
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There are multiple reasons why the C compiler cannot automatically reorder the fields:
The C compiler doesn't know whether the struct represents the memory structure of objects beyond the current compilation unit (for example: a foreign library, a file on disc, network data, CPU page ...
How to include external Python code to use in other files?
...ods in a file, is there a way to include those files in another file, but call them without any prefix (i.e. file prefix)?
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How do I write a short literal in C++?
...rt enough to compile this as if it's a short literal (i.e. it wouldn't actually allocate an int and then cast it every time).
The following illustrates how much you should worry about this:
a = 2L;
b = 2.0;
c = (short)2;
d = '\2';
Compile -> disassemble ->
movl $2, _a
movl $2, _b
m...
Get class name of django model
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Django models are derived from the ModelBase, which is the Metaclass for all models.
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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 "...