Struct Io 

pub struct Io<'a> {
    pub input: &'a mut (dyn BufRead + Send),
    pub out: &'a mut (dyn Write + Send),
    pub err: &'a mut (dyn Write + Send),
}

The streams a verb uses (real stdio in Cli::run, buffers in tests). Send, so mcp can read and write on their own threads.

Fields

input: &'a mut (dyn BufRead + Send)

out: &'a mut (dyn Write + Send)

err: &'a mut (dyn Write + Send)

Implementations

impl Io<'_>

pub fn reply(&mut self, r: &Reply) -> Exit

Print a reply line and turn it into an exit code.

pub fn fail(&mut self, json: bool, tool: &str, msg: impl Display) -> Exit

A failure: with json, the reply line on stdout (as Io::reply); without it, one line of plain text on stderr (<tool>: <message>), for a person reading a terminal.

pub fn reply_as(&mut self, json: bool, tool: &str, r: &Reply) -> Exit

A reply: with json the line on stdout; without it a success is the result as indented JSON on stdout and an error is plain text on stderr (see Io::fail).

pub fn usage(&mut self, msg: impl Display, usage: &str) -> Exit

A usage error: the reply line on stdout, a hint on stderr.