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belongs_to through associations
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What does the allow_nil do? Shouldn't an Employee always have a company?
– aaron-coding
Dec 24 '14 at 1:39
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Is it intended by the C++ standards committee that in C++11 unordered_map destroys what it inserts?
...he other overloads, and move constructing it into a value_type.
That is what some people call universal reference, but really is reference collapsing. In your case, where the argument is an lvalue of type pair<int,shared_ptr<int>> it will not result in the argument being an rvalue ref...
What is the purpose of the “Prefer 32-bit” setting in Visual Studio and how does it actually work?
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Microsoft has a blog entry What AnyCPU Really Means As Of .NET 4.5 and Visual Studio 11:
In .NET 4.5 and Visual Studio 11 the cheese has been moved. The
default for most .NET projects is again AnyCPU, but there is more than
one meaning to AnyCP...
What is the correct way of using C++11's range-based for?
What is the correct way of using C++11's range-based for ?
4 Answers
4
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What does the brk() system call do?
...ut crossing it.
The break is still the upper limit of the heap. However, what I didn't show is that there could be dozens of independent allocations of memory off there in the black somewhere, made with mmap instead of brk. (The OS will try to keep these far away from the brk area so they don't c...
What is the correct XPath for choosing attributes that contain “foo”?
Given this XML, what XPath returns all elements whose prop attribute contains Foo (the first three nodes):
9 Answers
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In Python, what is the difference between “.append()” and “+= []”?
What is the difference between:
12 Answers
12
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What is a predicate in c#? [duplicate]
... a and returns a % 2 == 0. This is essentially testing for an even number. What that means is:
pre(1) == false;
pre(2) == true;
And so on. This also means, if you have a List<int> ints and you want to find the first even number, you can just do this:
int firstEven = ints.Find(pre);
Of co...
PHP: exceptions vs errors?
Maybe I'm missing it somewhere in the PHP manual, but what exactly is the difference between an error and an exception? The only difference that I can see is that errors and exceptions are handled differently. But what causes an exception and what causes an error?
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When to use MongoDB or other document oriented database systems? [closed]
...and access patterns, but it’s built for your typical CRUD stuff. Storing what is essentially a huge hash, and being able to select on any of those keys, is what most people use a relational database for. If your DB is 3NF and you don’t do any joins (you’re just selecting a bunch of tables and ...