Exit Zen
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More formally, if the number:
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As an example, let's implement conversion for https://en.cppreference.com/w/cpp/chrono/system_clock[``std::chrono::system_clock::time_point``s] using https://en.wikipedia.org/wiki/ISO_8601[ISO 8601] format.
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The second, more powerful approach, is to provide the conversion implementation yourself. With Boost.JSON this is done by defining an overload of `tag_invoke` function (the benefits of this mechanism are outlined in http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1895r0.pdf[C++ proposal P1895]. In essence, `tag_invoke` provides a uniform interface for defining customization points by using argument-dependent lookup to find a viable overload from the point at which it is called. As the name suggests, a tag type is passed as an argument in order to:
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itself.
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If <<ref_try_value_to>> is used with a type, for which there's no `tag_invoke` overload of the form described in this section, but there is one of the form intended for <<ref_value_to>>, then the library still tries to perform the conversion. It uses the throwing overload, and attempts to convert any thrown exception into an {ref_error_code}. Note, though, that such approach will likely be slower then a dedicated overload.
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To avoid creating such temporaries with an incorrect {ref_memory_resource}, using <<ref_value>>'s member functions <<ref_value_emplace_array>>, <<ref_value_emplace_object>>, and <<ref_value_emplace_string>> can be helpful.
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similar to {std_string}.
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Formatted Output
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{ref_polymorphic_allocator} do not acquire ownership; the caller is responsible for ensuring that the lifetime of the resource extends until it is no longer referenced.
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The string provided by the
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is complicated and error-prone.
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<<ref_operator_eq_eq>> + <<ref_operator_not_eq>> + <<ref_operator_gt>> + <<ref_operator_gt_eq>> + <<ref_operator_lt>> + <<ref_operator_lt_eq>> + <<ref_operator_lt_lt>> +
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{ref_polymorphic_allocator} constructed from the {ref_memory_resource} used by the container. Ownership of this memory resource is not transferred.
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<<ref_parse_options>>
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When a <<ref_value>>, <<ref_array>>, or <<ref_object>> is assigned or constructed from an initializer list, the creation of the new value happens only once. This makes initializer lists equally efficient as using the other ways to create a value. The types in this library are first-class, supporting copy and move construction and assignment:
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*boost*
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{icon_bad} `basic_json` is a class template. Libraries must agree on the
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to a {std_ostream}.
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Initializer lists can be used to unambiguously construct or assign an <<ref_object>> or <<ref_array>>:
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`value_to` behavior
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