Zenth has a built-in Date type for working with calendar dates. Dates are created using static constructors and support formatting, addition, and subtraction.

#Creating Dates

#Today’s date

let d = Date.today();

Returns a Date object representing the current date (time portion is midnight UTC).

#From a string

let epoch = Date.from("1970-01-01");

Parses a date string using the default format %Y-%m-%d (year-month-day).

#From a string with custom format

let jan13 = Date.from("01/13/2007", "%m/%d/%Y");

The second argument is a Python-style format string. Available format specifiers:

#Formatting Dates

Use .format() with a Python-style format string:

let d = Date.from("2024-03-21");
Println(d.format("%Y-%m-%d"));    // 2024-03-21
Println(d.format("%d/%m/%Y"));    // 21/03/2024
Println(d.format("%B %d, %Y"));   // March 21, 2024

#Adding Time

Use .add(value) or .add(value, unit) to add time to a date. Returns a new Date (dates are immutable).

let d = Date.from("2024-03-21");

// Default unit is "days"
let tomorrow = d.add(1);           // 2024-03-22
let next_week = d.add(7);          // 2024-03-28

// Explicit units
let next_month = d.add(1, "months");  // 2024-04-21
let next_year = d.add(1, "years");    // 2025-03-21

Supported units: "days" (default), "months", "years".

#Subtracting Time

Use .sub(value) or .sub(value, unit) to subtract time from a date. Returns a new Date.

let d = Date.from("2024-03-21");

let yesterday = d.sub(1);             // 2024-03-20
let last_month = d.sub(1, "months");  // 2024-02-21
let last_year = d.sub(1, "years");    // 2023-03-21

#Chaining

All date methods return new Date objects, so calls can be chained:

let d = Date.today().add(1, "years").add(3, "months").add(10);
Println(d.format("%Y-%m-%d"));

#Converting to String

Use .format() for controlled output. Str() works but returns Go’s verbose time format:

let d = Date.from("2024-03-21");
Println(d.format("%Y-%m-%d"));   // "2024-03-21" (preferred)
Println(Str(d));                  // "2024-03-21 00:00:00 +0000 UTC" (verbose)

#Complete Example

fn main() {
    let today = Date.today();
    Println("Today: " + today.format("%B %d, %Y"));

    let deadline = today.add(30);
    Println("Deadline: " + deadline.format("%Y-%m-%d"));

    let epoch = Date.from("1970-01-01");
    let y2k = epoch.add(30, "years");
    Println("Y2K: " + y2k.format("%Y-%m-%d"));
}