Function extern_spec_Sub_i64_i64_sub 

pub fn extern_spec_Sub_i64_i64_sub(self_: i64, rhs: i64) -> i64

extern spec for i64::sub

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

requires

$type::MIN@ <= self@ $op rhs@ && self@ $op rhs@ <= $type::MAX@

ensures

result@ == self@ $op rhs@