Function extern_spec_T_A_VecDeque_T_A_push_back 

pub fn extern_spec_T_A_VecDeque_T_A_push_back<T, A: Allocator>(
    self_: &mut VecDeque<T, A>,
    value: T,
)

extern spec for VecDeque<T, A>::push_back

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

terminates

ensures

(^self)@ == self@.push_back(value)