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    std::meta::reflect_constant_array

    From cppreference.com
    < cpp | meta
     
    C++
     
    Metaprogramming library
    Type traits
    Compile-time rational arithmetic
    Compile-time integer sequences
    (C++14)
    Compile-time reflection
     
    Defined in header <meta> 
    template< ranges::input_range R >
consteval std::meta::info reflect_constant_array( R&& r );
    		(since C++26)

    Returns a reflection that represents an array object whose elements are corresponding elements of r.

    The resulting object is a template parameter object: it has static storage duration, and ranges with template-argument-equivalent contents correspond to the same object.

    If the size of r is not zero, the resulting array object is a potentially non-unique object.

    Let U be ranges::range_value_t<R> and T be std::remove_all_extents_t<U>.

    The program is ill-formed if any of the following is true:

    Parameters

    r - an input_range

    Return value

    If the size of r is not zero, a reflection that represents a template parameter object of type const T[N] (where N is the size of r). Each element of the template parameter object is template-argument-equivalent to:

    • std::meta::reflect_constant_array(*it) if U is an array type;
    • std::meta::reflect_constant(static_cast<T>(*it)) otherwise;

    where it is an iterator to the corresponding element of r.

    Otherwise (the size of r is zero), a reflection that represents the template parameter object of type const std::array<T, 0> initialized with {}.

    Exceptions

    Throws any exception thrown by:

    • an operation on r or on iterators or sentinels of r;
    • any argument of std::meta::reflect_constant or any call of std::meta::reflect_constant_array described above.

    Throws std::meta::exception if any invocation of std::meta::reflect_constant would exit via an exception.

    Notes

    The result of std::meta::reflect_constant_array is suitable for use with std::meta::substitute. If the caller wants a std::span of a static array, as opposite to a reflection value, std::define_static_array is usually more suitable.

    Example

    This section is incomplete
    Reason: no example

    See also

    (C++26)
    		 promotes compile-time array into static storage, returning a span of the static array
    (function template) [edit]
    (C++26)
    		 promotes a compile-time string to static storage, returning a reflection representing the static string
    (function template) [edit]
    (C++26)
    		 returns a reflection representing a value or template parameter object, suitable for use as a constant template argument
    (function template) [edit]