Boost C++ Libraries

Parse a buffer containing all or part of a complete JSON.

std::size_t
write_some(
    char const* data,
    std::size_t size,
    std::error_code& ec);

This function parses JSON contained in the specified character buffer. If parsing completes, any additional characters past the end of the complete JSON are ignored. The function returns the actual number of characters parsed, which may be less than the size of the input. This allows parsing of a buffer containing multiple individual JSONs or containing different protocol data.

stream_parser p;                                // construct a parser
std::size_t n;                                  // number of characters used
n = p.write_some( "[1,2" );                     // parse the first part of the JSON
assert( n == 4 );                               // all characters consumed
n = p.write_some( "3,4] null" );                // parse the rest of the JSON
assert( n == 5 );                               // only some characters consumed
value jv = p.release();                         // take ownership of the value

To indicate there are no more character buffers, such as when done returns false after writing, call finish.

Linear in size.

Basic guarantee. Calls to memory_resource::allocate may throw. Upon error or exception, subsequent calls will fail until reset is called to parse a new JSON.

The number of characters consumed from the buffer.