sbepp::cursor_ops Namespace Reference

Contains cursor wrappers which allow more precise control over its position. More...

Functions
template<typename Byte >
constexpr detail::init_cursor_wrapper< Byte >	init (cursor< Byte > &c) noexcept
	Returns a wrapper which will initialize the cursor when it's used and advance after the usage.
template<typename Byte >
constexpr detail::dont_move_cursor_wrapper< Byte >	dont_move (cursor< Byte > &c) noexcept
	Returns a wrapper which doesn't advance the cursor when it's used.
template<typename Byte >
constexpr detail::init_dont_move_cursor_wrapper< Byte >	init_dont_move (cursor< Byte > &c) noexcept
	Returns a wrapper which initializes the cursor but doesn't move it. Behaves like a combination of init() and dont_move().
template<typename Byte >
constexpr detail::skip_cursor_wrapper< Byte >	skip (cursor< Byte > &c) noexcept
	Returns a wrapper which moves the cursor to the end of field/group/data without returning the accessed value.

Detailed Description

Contains cursor wrappers which allow more precise control over its position.

Function Documentation

dont_move()

template<typename Byte >

constexpr detail::dont_move_cursor_wrapper< Byte > sbepp::cursor_ops::dont_move ( cursor< Byte > & c )

constexprnoexcept

Returns a wrapper which doesn't advance the cursor when it's used.

Allows to access field/group/data more than once using cursor API. Useful to read and write the same field or to write data member. Example:

schema::messages::msg1<char> m{ptr, size};
auto c = sbepp::init_cursor(m);
// use but don't advance, otherwise we can't access `field` again
auto value = m.field(sbepp::cursor_ops::dont_move(c));
m.field(*value + 1, c);
// since data has unknown size, without `dont_move` cursor will be moved
// to a random position
auto d = m.data(sbepp::cursor_ops::dont_move(c));
d.resize(1); // init data somehow
m.data(c);   // advance the cursor

Parameters

c	original cursor

Returns

unspecified cursor wrapper

init()

template<typename Byte >

constexpr detail::init_cursor_wrapper< Byte > sbepp::cursor_ops::init ( cursor< Byte > & c )

constexprnoexcept

Returns a wrapper which will initialize the cursor when it's used and advance after the usage.

Allows to start using cursor API from any field/group/data. Example:

schema::messages::msg1<char> m{ptr, size};
sbepp::cursor<char> c;   // Note: not initialized
// initialize, use, advance
auto first = m.firstField(sbepp::cursor_ops::init(c));
auto second = m.secondField(c); // continue as usual

Parameters

c	original cursor

Returns

unspecified cursor wrapper

init_dont_move()

template<typename Byte >

constexpr detail::init_dont_move_cursor_wrapper< Byte > sbepp::cursor_ops::init_dont_move ( cursor< Byte > & c )

constexprnoexcept

Returns a wrapper which initializes the cursor but doesn't move it. Behaves like a combination of init() and dont_move().

Parameters

c	original cursor

Returns

unspecified cursor wrapper

skip()

template<typename Byte >

constexpr detail::skip_cursor_wrapper< Byte > sbepp::cursor_ops::skip ( cursor< Byte > & c )

constexprnoexcept

Returns a wrapper which moves the cursor to the end of field/group/data without returning the accessed value.

Allows to skip uninteresting members. Example:

schema::messages::msg1<char> m{ptr, size};
auto c = sbepp::init_cursor(m);
m.group(sbepp::cursor_ops::skip(c)); // skip the whole group
auto d = m.data(c);  // access next member

Parameters

c	original cursor

Returns

unspecified cursor wrapper