Macro fa_dt64 

macro_rules! fa_dt64 {
    ($name:expr, $unit:expr; @vec64 $v:expr $(,)?) => { ... };
    ($name:expr, $unit:expr; $first:expr, $($rest:expr),+ $(,)?) => { ... };
    ($name:expr, $unit:expr; $v:expr $(,)?) => { ... };
    ($name:expr, $unit:expr;) => { ... };
}

Build a named FieldArray of i64-backed datetimes.

The time unit is required. It follows the column name and is separated from the values by ;.

use minarrow::{fa_dt64, vec64, TimeUnit};
let a = fa_dt64!("ts", TimeUnit::Seconds; 1_768_521_600, 1_775_865_600);
let b = fa_dt64!("ts", TimeUnit::Seconds; 1_768_521_600);
let c = fa_dt64!("ts", TimeUnit::Milliseconds; @vec64 vec64![1, 2, 3]);
let d = fa_dt64!("ts", TimeUnit::Seconds;);