node.hpp

//
// Copyright 2022 romanf
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//
// Implementations of consteval constructors for various types of nodes.
// It currently requires C++17 because of string_view, but may be tuned
// down to C++11 with some modifications.
//

#ifndef _NODE_HPP_
#define _NODE_HPP_

#include "node.h"

static_assert(sizeof(Node) == SizeOfNode);

template<typename T> consteval _NodePayload::_NodePayload(const T* p):
    ptr(static_cast<const void*>(p)) {}

consteval _NodePayload::_NodePayload(std::uint64_t n): 
    num(n) {}

consteval _NodeDescriptor::_NodeDescriptor(NodeType t, size_t l, size_t s): 
    len(l), 
    sz(s), 
    id(t) {}

consteval Node::Node(const std::string_view& n, uint64_t value):
    name(std::data(n)), 
    payload(value),
    type(Number, 1, sizeof(value)) {}

template<typename T> consteval NodeType Node::TypeToId() {
    return std::is_same<T, char>::value ? 
        String :
        std::is_same<T, Node>::value ? 
            Folder :
            Blob;
}

template<typename T, size_t N> consteval Node::Node(const std::string_view& n, const T (&s)[N]):
    name(std::data(n)),
    payload(std::data(s)),
    type(TypeToId<T>(), N, sizeof(T)) {}

#define SET_ROOT(folder) \
    extern "C" constexpr Node root("/", (folder)); \
    static_assert(root.type.id == Folder)
#endif