dh

Trait Seekable

source 
pub trait Seekable: Seek {
    // Provided methods
    fn rewind(&mut self) -> Result<u64> { ... }
    fn end(&mut self) -> Result<u64> { ... }
    fn to(&mut self, pos: u64) -> Result<u64> { ... }
    fn jump(&mut self, pos: i64) -> Result<u64> { ... }
    fn size(&mut self) -> Result<u64> { ... }
    fn pos(&mut self) -> Result<u64> { ... }
}
Expand description

Provides methods to seek a stream.

This trait is automatically implemented for any type that implements Seek, that includes any type that implements Readable, Writable and Rw as all these traits require Seek to be implemented.

Provided Methods§

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fn rewind(&mut self) -> Result<u64>

Sets the stream position to the beginning. This is the same as calling to with 0.

§Example
use dh::recommended::*;

let mut writer = dh::data::write_new(2);

writer.write_u8(0x80).unwrap(); // reads the first byte
assert_eq!(writer.pos().unwrap(), 1);

writer.rewind().unwrap(); // sets the position to the beginning
assert_eq!(writer.pos().unwrap(), 0);
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fn end(&mut self) -> Result<u64>

Sets the stream position to the end. It is not recommended to read anything after this because it would result in an EOF error.

§Example
use dh::recommended::*;

let mut writer = dh::data::write_new(2);

writer.end().unwrap(); // sets the position to the end
assert_eq!(writer.pos().unwrap(), 2);
source

fn to(&mut self, pos: u64) -> Result<u64>

Sets the stream position to a specific position.

§Example
use dh::recommended::*;

let mut writer = dh::data::write_new(2);

writer.to(1).unwrap(); // sets the position to the second byte
assert_eq!(writer.pos().unwrap(), 1);
source

fn jump(&mut self, pos: i64) -> Result<u64>

Jumps a specific amount of bytes from the current position.

§Example
use dh::recommended::*;

let mut writer = dh::data::write_new(2);

writer.to(1).unwrap(); // sets the position to the second byte

writer.jump(1).unwrap(); // sets the position to the next byte
assert_eq!(writer.pos().unwrap(), 2);

writer.jump(-1).unwrap(); // sets the position to the previous byte
assert_eq!(writer.pos().unwrap(), 1);
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fn size(&mut self) -> Result<u64>

Calculates the current size of the source. Please call this method as less as possible because it moves to the end of the stream and back to the previous position. If you need to know the size of the source, consider storing it in a variable.

§Example
use dh::recommended::*;

let mut writer = dh::data::write_new(2);

assert_eq!(writer.size().unwrap(), 2);
source

fn pos(&mut self) -> Result<u64>

Returns the current position of the stream.

§Example
use dh::recommended::*;

let mut writer = dh::data::write_new(2);

writer.write_u8(0x80).unwrap(); // reads the first byte
assert_eq!(writer.pos().unwrap(), 1);

Implementors§