Trait Cursor 

pub trait Cursor {
    type Offset;
    type Item;

    // Required methods
    fn get_offset(&self) -> Self::Offset;
    fn set_offset(&mut self, offset: Self::Offset);
    fn get(&self) -> Option<Self::Item>;
    fn advance(&mut self, direction: Direction) -> Result<bool>;

    // Provided method
    fn next(&mut self, direction: Direction) -> Result<Option<Self::Item>> { ... }
}

A read-only Iterator that can move back and forth.

Required Associated Types

type Offset

type Item

Required Methods

fn get_offset(&self) -> Self::Offset

Get offset of the cursor.

fn set_offset(&mut self, offset: Self::Offset)

Set offset of the cursor.

fn get(&self) -> Option<Self::Item>

Get the item pointed to by the cursor. Could be None if item is invalid.

fn advance(&mut self, direction: Direction) -> Result<bool>

Move the cursor one step in the given direction if it’s within range. Return if the cursor is moved.

Provided Methods

fn next(&mut self, direction: Direction) -> Result<Option<Self::Item>>

Move the cursor in the given direction until a valid item is obtained. If no more valid item available, return None and offset unchanged.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl Cursor for StoreCursor

type Offset = StoreOffset

type Item = (SystemTime, DataFrame)