Can metaprogramming techniques be used to programmatically assign values to static arrays at compile time in C ?

Programmatic Array Creation at Compile Time in C

C provides the ability to define static arrays at compile time using explicit declarations like:

const std::size_t size = 5;    
unsigned int list[size] = { 1, 2, 3, 4, 5 };

Question 1: Programmatic Value Assignment

Can metaprogramming techniques be utilized to assign values to these elements programmatically at compile time?

Answer:

C 0x introduces the concept of template variadic arguments, allowing the initialization of arrays from a variable number of arguments. However, template instantiation depth limits the practicality of this approach for large arrays.

Question 2: Selective Value Assignment

Assuming most array elements are the same, can values be selectively assigned in a programmatic manner at compile time?

Answer:

A more refined approach utilizes C 0x metafunctions and template specialization to generate arrays with interspersed values. This involves a recursive template struct generate_array and a custom metafunction MetaFunc to define element values.

template<size_t index> struct MetaFunc { 
    enum { value = index + 1 }; 
};

void test() {
    const size_t count = 5;
    typedef generate_array<count metafunc>::result A;

    for (size_t i=0; i<count std::cout a::data><p>This solution involves recursive template instantiation and is suitable for arrays of limited size due to template depth limitations.</p></count></count></size_t>

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