basic_csv_cursor.md

jsoncons::csv::basic_csv_cursor

#include <jsoncons_ext/csv/csv_cursor.hpp>

template<
    class CharT,
    class Source=jsoncons::stream_source<CharT>,
    class Allocator=std::allocator<char>> basic_csv_cursor;

A pull parser for reporting CSV parse events. A typical application will repeatedly process the current() event and call the next() function to advance to the next event, until done() returns true. In addition, when positioned on a begin_object event, the read_to function can pull a complete object representing the events from begin_object to end_object, and when positioned on a begin_array event, a complete array representing the events from begin_array ro end_array.

basic_csv_cursor is noncopyable and nonmoveable.

Aliases for common character types are provided:

Type	Definition
csv_stream_cursor (since 0.167.0)	basic_csv_cursor<char,csvcons::stream_source<char>>
csv_string_cursor (since 0.167.0)	basic_csv_cursor<char,csvcons::string_source<char>>
wcsv_stream_cursor (since 0.167.0)	basic_csv_cursor<wchar_t,csvcons::stream_source<wchar_t>>
wcsv_string_cursor (since 0.167.0)	basic_csv_cursor<wchar_t,csvcons::string_source<wchar_t>>
csv_cursor (until 0.167.0)	basic_csv_cursor<char>
wcsv_cursor (until 0.167.0)	basic_csv_cursor<wchar_t>

Implemented interfaces

basic_staj_cursor

Constructors

template <typename Sourceable>
basic_csv_cursor(Sourceable&& source, 
                 const basic_csv_decode_options<CharT>& options = basic_csv_decode_options<CharT>(),
                 std::function<bool(csv_errc,const ser_context&)> err_handler = default_csv_parsing(),
                 const Allocator& alloc = Allocator()); (1)

template <typename Sourceable>
basic_csv_cursor(Sourceable&& source, 
                 std::error_code& ec); (2)

template <typename Sourceable>
basic_csv_cursor(Sourceable&& source, 
                 const basic_csv_decode_options<CharT>& options,
                 std::error_code& ec); (3)

template <typename Sourceable>
basic_csv_cursor(Sourceable&& source, 
                 const basic_csv_decode_options<CharT>& options,
                 std::function<bool(csv_errc,const ser_context&)> err_handler,
                 std::error_code& ec); (4)

template <typename Sourceable>
basic_csv_cursor(std::allocator_arg_t, const Allocator& alloc, 
                 Sourceable&& source, 
                 const basic_csv_decode_options<CharT>& options,
                 std::function<bool(csv_errc,const ser_context&)> err_handler,
                 std::error_code& ec); (5)

Constructors (1) reads from a character sequence or stream and throws a ser_error if a parsing error is encountered while processing the initial event.

Constructors (2)-(5) read from a character sequence or stream and set ec if a parsing error is encountered while processing the initial event.

Note: It is the programmer's responsibility to ensure that basic_csv_cursor does not outlive the source
passed in the constuctor, as basic_csv_cursor holds pointers to but does not own this resource.

Parameters

source - a value from which a jsoncons::basic_string_view<char_type> is constructible, or a value from which a source_type is constructible. In the case that a jsoncons::basic_string_view<char_type> is constructible from source, source is dispatched immediately to the parser. Otherwise, the csv_cursor reads from a source_type in chunks.

Member functions

bool done() const override;

Checks if there are no more events.

const basic_staj_event& current() const override;

Returns the current basic_staj_event.

void read_to(json_visitor& visitor) override

Feeds the current and succeeding staj events through the provided visitor, until the visitor indicates to stop. If a parsing error is encountered, throws a ser_error.

void read_to(basic_json_visitor<char_type>& visitor,
            std::error_code& ec) override

Feeds the current and succeeding staj events through the provided visitor, until the visitor indicates to stop. If a parsing error is encountered, sets ec.

void next() override;

Advances to the next event. If a parsing error is encountered, throws a ser_error.

void next(std::error_code& ec) override;

Advances to the next event. If a parsing error is encountered, sets ec.

const ser_context& context() const override;

Returns the current context

void reset();

Reset cursor to read another value from the same source

template <typename Sourceable>
reset(Sourceable&& source)

Reset cursor to read new value from a new sources

Non-member functions

template <typename CharT,typename Source,typename Allocator> basic_staj_filter_view operator|(basic_csv_cursor<CharT,Source,Allocator>& cursor, std::function<bool(const basic_staj_event&, const ser_context&)> pred);

Examples

See also

basic_staj_event

staj_array_iterator

staj_object_iterator