fn checked_add_u64_i64(a: u64, b: i64) -> Option<u64> {
    if b > 0 {
        a.checked_add(b as u64)
    } else if b < 0 {
        a.checked_sub(-b as u64)
    } else {
        Some(a)
    }
}
/// Performs a checked unsigned signed addition.
Performs a checked unsigned signed addition.
Performs a checked unsigned signed addition .
fn checked_add_u64_i64(a: u64, b: i64) -> Option<u64> {
    if b > 0 {
        a.checked_add(b as u64)
    } else if b < 0 {
        a.checked_sub(-b as u64)
    } else {
        Some(a)
    }
}
fn checked_add_u64_i64 ( a : u64 , b : i64 ) -> Option < u64 > { if b > 0 { a . checked_add ( b as u64 ) } else if b < 0 { a . checked_sub ( - b as u64 ) } else { Some ( a ) } }
Performs a checked unsigned signed addition.
Performs a checked unsigned signed addition .
a
u64
b
i64
a
u64
b
i64