[/
    Copyright (c) 2023 Dmitry Arkhipov (grisumbras@yandex.ru)

    Distributed under the Boost Software License, Version 1.0. (See accompanying
    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

    Official repository: https://github.com/boostorg/json
]

[/-----------------------------------------------------------------------------]


[section Direct parsing]

For large inputs parsing into the library's containers followed by conversion
via __value_to__ might be prohibitively expensive. For this cases the library
provides components that allow parsing directly into user-provided objects.

The drawback of this approach is that fully custom type representations are
not supported, only the library-provided conversions are. Also all objects that
should be populated by parsing have to be default constructible types. This
includes not only the top-level object, but e.g. elements of containers,
members of described `struct`s, and alternatives of variants.

That being said, if your types are default-constructible and you don't need
the customisability allowed by __value_to__, then you can get a significant
performance boost with direct parsing.

Direct parsing is performed by the __parse_into__ family of functions. The
library provides overloads that take either __string_view__ or `std::istream`,
and can report errors either via throwing exceptions or setting an error code.

[doc_parse_into_1]

Finally, if you need to combine incremental parsing with direct parsing, you
can resort to __parser_for__. `parser_for<T>` is an instantiation of
__basic_parser__ that parses into an object of type `T`, and is what
__parse_into__ uses under the hood.

[endsect]
