Note that rust has bit literals, so you can explicitly write bit masks out: let mask = if blah { 0b11111110000000001001001100000101u64 } else { 0 } and yo

Note that rust has bit literals, so you can explicitly write bit masks out: let mask = if blah { 0b11111110000000001001001100000101u64 } else { 0 } and you can include optional underscores wherever for clarity let mask = if blah { 0b_11111110_00000000_10010011_00000101_u64 } else { !0 }