Feng
Manual contents

Time and Math

Math Functions

Import std.numeric to use Math:

import std.numeric;

let distance = Math.sqrt(9.0);
let angle = Math.sin(0.5);
let bounded = Math.max(0.0, Math.min(1.0, value));

Math operates on f64 and covers absolute values, minimum and maximum, trigonometric and hyperbolic functions, exponentials, logarithms, powers, square roots, rounding, and remainders.

DateTime

Import std.time:

import std.time;

let now = DateTime.now();
let release = DateTime.of((i32)2026, (i32)8, (i32)1);
let tomorrow = now.addDays((i64)1);

println(now.toString());
println(release.toDateString());

DateTime is an immutable value object without time-zone information. Methods that modify a component return a new value:

  • addYears, addMonths, addDays, addHours, and related methods perform date and time arithmetic.
  • withYear, withMonth, withDay, and related methods replace one component.
  • isBefore, isAfter, equals, and compareTo compare values.
  • toMilliseconds, toSeconds, and their corresponding from... methods convert timestamps.

DateTime.now() returns the current UTC time. When displaying local time to a user, handle time-zone requirements explicitly rather than treating a value without a time zone as local time.