Trait crossterm::QueueableCommand

pub trait QueueableCommand {
    fn queue(&mut self, command: impl Command) -> Result<&mut Self>;
}

An interface for types that can queue commands for further execution.

Required methods

fn queue(&mut self, command: impl Command) -> Result<&mut Self>

Queues the given command for further execution.

Implementors

impl<T: Write + ?Sized> QueueableCommand for T

fn queue(&mut self, command: impl Command) -> Result<&mut Self>

Queues the given command for further execution.

Queued commands will be executed in the following cases:

• When flush is called manually on the given type implementing io::Write.
• The terminal will flush automatically if the buffer is full.
• Each line is flushed in case of stdout, because it is line buffered.

Arguments

• Command

  The command that you want to queue for later execution.

Examples

use std::io::{Write, stdout};

use crossterm::{Result, QueueableCommand, style::Print};

 fn main() -> Result<()> {
    let mut stdout = stdout();

    // `Print` will executed executed when `flush` is called.
    stdout
        .queue(Print("foo 1\n".to_string()))?
        .queue(Print("foo 2".to_string()))?;

    // some other code (no execution happening here) ...

    // when calling `flush` on `stdout`, all commands will be written to the stdout and therefore executed.
    stdout.flush()?;

    Ok(())

    // ==== Output ====
    // foo 1
    // foo 2
}

Have a look over at the Command API for more details.

Notes

• In the case of UNIX and Windows 10, ANSI codes are written to the given ‘writer’.
• In case of Windows versions lower than 10, a direct WinAPI call will be made. The reason for this is that Windows versions lower than 10 do not support ANSI codes, and can therefore not be written to the given writer. Therefore, there is no difference between execute and queue for those old Windows versions.