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c++genericsgeneric-programming

Can a generic function be used for summing structs?


Suppose I have a struct, such as:

struct Foo {
    double a;
    float b;
    int c;
};

Summing fooA and fooB (both of type Foo) would equate to:

{fooA.a + fooB.a, 
 fooA.b + fooB.b, 
 fooA.c + fooB.c};

Now my question is, could a generic function be created that would sum structs together in this manner? i.e.:

template <typename StructType>
StructType sumStructs(StructType A, StructType B) {
    // sum component with one another, return resulting struct
}

Alternatively, what limitations would you need to impose for it to be possible?


Solution

  • As Joachim Pileborg put it,

    No, C++ doesn't have introspection so there is no way to get structure members of unknown structures.

    So what I ended up doing was overloading + for each struct individually. This in turn allowed me to create a generic function that takes a node, and sums all of its parent structs (useful, for example, for summing positions, to get the absolute position of an object).