pub fn shutdown(&self) {
        // hang up the channel which will cause the dedicated thread
        // to quit
        let mut state = self.state.lock();
        state.requests = None;
    }
/// signals shutdown of this executor and any Clones
signals shutdown of this executor and any Clones
signals shutdown of this executor and any Clones
pub fn shutdown(&self) {
        // hang up the channel which will cause the dedicated thread
        // to quit
        let mut state = self.state.lock();
        state.requests = None;
    }
pub fn shutdown ( & self ) { // hang up the channel which will cause the dedicated thread // to quit let mut state = self . state . lock ( ) ; state . requests = None ; }
signals shutdown of this executor and any Clones
signals shutdown of this executor and any Clones
&self
&self