Function extern_spec_T_Option_T_as_mut 

pub fn extern_spec_T_Option_T_as_mut<T>(self_: &mut Option<T>) -> Option<&mut T>

extern spec for Option<T>::as_mut

This is not a real function: its only use is for documentation.

ghost

ensures

self == None ==> result == None && ^self

ensures

self == None
         || exists<r: &mut T> result == Some(r) && *self == Some(*r) && ^self