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Defined in header <fkYAML/node.hpp>

fkyaml::ordered_map::at

template <
    typename KeyType,
    detail::enable_if_t<detail::is_usable_as_key_type<key_compare, key_type, KeyType>::value, int> = 0>
mapped_type& at(KeyType&& key) noexcept;

template <
    typename KeyType,
    detail::enable_if_t<detail::is_usable_as_key_type<key_compare, key_type, KeyType>::value, int> = 0>
const mapped_type& at(KeyType&& key) const

Accesses an element with the given key.
This API throws a [fkyaml::exception] if the given key does not exist in the ordered_map object.

Template Parameters

KeyType
A type compatible with the key type.

Parameters

key [in]
A key to the target value.

Return Value

Reference, or constant reference, to a mapped_type object associated with the given key.

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

int main() {
    fkyaml::ordered_map<std::string, fkyaml::node> om = {{"foo", 123}, {"bar", "baz"}};

    std::cout << om.at("foo") << std::endl;
    std::cout << om.at("bar") << std::endl;

    // accesses with a unknown key will throw an exception.
    try {
        fkyaml::node& n = om.at("baz");
    }
    catch (const fkyaml::exception& e) {
        std::cout << e.what() << std::endl;
    }

    return 0;
}

output: 

123
baz
key not found.

See Also