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Defined in header <fkYAML/node.hpp>

fkyaml::basic_node::begin, fkyaml::basic_node::cbegin

map_range map_items();
const_map_range map_items() const;

Returns a (constant) range of mapping entries.
If a basic_node is not a mapping, a fkyaml::type_error will be thrown.

This function allows accessing the key() and value() functions provided by iterator and const_iterator in range-based for loops:

// without map_items()
for (auto it : mapping) {
    // `it` is of type fkyaml::node::reference and has no key() member function.
    std::cout << "value: " << it << std::endl;
}

// with map_items()
for (auto it : mapping.map_items()) {
    // `it` is now of type fkyaml::node::iterator and has key() member function.
    std::cout << "key: " << it.key() << ", value: " << it.value() << std::endl;
}

Also, this function allows using structured bindings (since C++17):

for (auto& [key, value] : mapping.map_items()) {
    // `key` and `value` are both of type fkyaml::node::reference.
    std::cout << "key: " << key << ", value: " << value << std::endl;
}

Return Value

A (constant) iterator to the first element of a container node.

Examples

Example 
#include <iostream>
#include <fkYAML/node.hpp>

int main() {
    // create a mapping node.
    fkyaml::node map_node = {{"foo", 123}, {"bar", true}};

    // print all the mapping entries.
    for (auto it : map_node.map_items()) {
        std::cout << "key: " << it.key() << ", value: " << it.value() << std::endl;
    }

    fkyaml::node seq_node = {123, false, 3.14};
    try {
        // map_items() cannot be called on a sequence node.
        auto invalid = seq_node.map_items();
    }
    catch (const fkyaml::exception& e) {
        std::cout << e.what() << std::endl;
    }

    return 0;
}

output: 

key: bar, value: true
key: foo, value: 123
type_error: map_items() cannot be called on a non-mapping node. type=SEQUENCE

See Also