Function extern_spec_SubAssign__ref_u64_u64_sub_assign 

pub fn extern_spec_SubAssign__ref_u64_u64_sub_assign(self_: &mut u64, rhs: &u64)

extern spec for u64::sub_assign

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

requires

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

ensures

(^self)@ == self@ $op rhs@