Macro from_ns 

macro_rules! from_ns {
    ($ns:expr, $frac:expr, on=$scale:expr, target=$target:expr) => { ... };
    ($ns:expr, $frac:expr, target=$target:expr, on=$scale:expr) => { ... };
    ($ns:expr, on=$scale:expr, target=$target:expr) => { ... };
    ($ns:expr, target=$target:expr, on=$scale:expr) => { ... };
    ($ns:expr, $frac:expr, on=$scale:expr) => { ... };
    ($ns:expr, $frac:expr, target=$target:expr) => { ... };
    ($ns:expr, on=$scale:expr) => { ... };
    ($ns:expr, target=$target:expr) => { ... };
    ($ns:expr, $frac:expr) => { ... };
    ($ns:expr) => { ... };
}

Builds a Dt from whole nanoseconds and an optional signed fractional remainder in attoseconds.

• Equivalent to Dt::from_ns.
• Does not perform time-scale conversion.

The fractional remainder is in attoseconds — use ps! (or another *_to_attos helper) instead of writing the attosecond literal by hand.

Defaults

Omitted	Default
fraction	0
on and target	both Scale::TAI
only on=s	target=s
only target=t	on=TAI

Forms

from_ns!(ns)
from_ns!(ns, frac)
from_ns!(ns, on=s)
from_ns!(ns, target=t)
from_ns!(ns, on=s, target=t)
from_ns!(ns, target=t, on=s)
from_ns!(ns, frac, on=s)
from_ns!(ns, frac, target=t)
from_ns!(ns, frac, on=s, target=t)
from_ns!(ns, frac, target=t, on=s)

Examples

use deep_time::{Dt, Scale, macros::from_ns, macros::ps};

// 1.3 ns → whole nanoseconds + 300 ps remainder
let a = from_ns!(1);
let b = from_ns!(1, ps!(300));
let c = from_ns!(-1, ps!(-300), on=Scale::TAI);
let d = from_ns!(0, on=Scale::UTC);
let e = from_ns!(1, on=Scale::TAI, target=Scale::UTC);
let f = from_ns!(1, target=Scale::UTC);

assert_eq!(a, Dt::from_ns(1, 0, Scale::TAI, Scale::TAI));
assert_eq!(b, Dt::from_ns(1, ps!(300), Scale::TAI, Scale::TAI));
assert_eq!(c, Dt::from_ns(-1, ps!(-300), Scale::TAI, Scale::TAI));
assert_eq!(d, Dt::from_ns(0, 0, Scale::UTC, Scale::UTC));
assert_eq!(e, Dt::from_ns(1, 0, Scale::TAI, Scale::UTC));
assert_eq!(f, e);

let signed = from_ns!(-1, ps!(-300));
let floor = from_ns!(-2, ps!(700));
assert_eq!(signed, floor);
assert_eq!(signed, Dt::from_ns(-1, ps!(-300), Scale::TAI, Scale::TAI));