pub fn downcast_mut<E: Display + Debug + Send + Sync + 'static>(&mut self) -> Option<&mut E> {
        if self.is::<E>() {
            unsafe { Some(&mut *(self.inner.error_mut() as *mut dyn Error as *mut E)) }
        } else { None }
    }
/// Downcast this exception by mutable reference.
Downcast this exception by mutable reference.
Downcast this exception by mutable reference .
pub fn downcast_mut<E: Display + Debug + Send + Sync + 'static>(&mut self) -> Option<&mut E> {
        if self.is::<E>() {
            unsafe { Some(&mut *(self.inner.error_mut() as *mut dyn Error as *mut E)) }
        } else { None }
    }
pub fn downcast_mut < E : Display + Debug + Send + Sync + ' static > ( & mut self ) -> Option < & mut E > { if self . is :: < E > ( ) { unsafe { Some ( & mut * ( self . inner . error_mut ( ) as * mut dyn Error as * mut E ) ) } } else { None } }
Downcast this exception by mutable reference.
Downcast this exception by mutable reference .
&mut self