Trait icu_datetime::input::DateTimeInput

source · 
pub trait DateTimeInput: DateInput + IsoTimeInput { }
Expand description

A combination of a formattable calendar date and ISO time.

§Examples

If the trait does not return all required fields, an error output will occur:

use icu::calendar::*;
use icu::calendar::types::*;
use icu::datetime::input::*;
use icu::datetime::{DateTimeWriteError, TypedDateTimeNames};
use icu::datetime::fields::{Field, FieldLength, FieldSymbol, Weekday};
use icu::datetime::neo_pattern::DateTimePattern;
use icu::locid::locale;
use writeable::assert_try_writeable_eq;

struct Empty;

impl DateInput for Empty {
    type Calendar = Gregorian;
    fn year(&self) -> Option<FormattableYear> { None }
    fn month(&self) -> Option<FormattableMonth> { None }
    fn day_of_month(&self) -> Option<DayOfMonth> { None }
    fn iso_weekday(&self) -> Option<IsoWeekday> { None }
    fn day_of_year_info(&self) -> Option<DayOfYearInfo> { None }
    fn any_calendar_kind(&self) -> Option<AnyCalendarKind> { None }
    fn to_iso(&self) -> icu::calendar::Date<Iso> { todo!() }
}

impl IsoTimeInput for Empty {
    fn hour(&self) -> Option<IsoHour> { None }
    fn minute(&self) -> Option<IsoMinute> { None }
    fn second(&self) -> Option<IsoSecond> { None }
    fn nanosecond(&self) -> Option<NanoSecond> { None }
}

// Create an instance that can format abbreviated month, weekday, and day period names:
let mut names: TypedDateTimeNames<Gregorian> =
    TypedDateTimeNames::try_new(&locale!("en").into()).unwrap();

// Create a pattern from a pattern string:
let pattern_str = "'It is:' E MMM d y G 'at' h:mm:ssSSS a";
let pattern: DateTimePattern = pattern_str.parse().unwrap();

// The pattern string contains lots of symbols, but our DateTimeInput is empty!
let mut buffer = String::new();
// Missing data is filled in on a best-effort basis, and an error is signaled.
assert_try_writeable_eq!(
    names.with_pattern(&pattern).format(&Empty),
    "It is: {E} {M} {d} {y} {G} at {h}:{m}:{s}{S} {a}",
    Err(DateTimeWriteError::MissingInputField("iso_weekday"))
);

Implementors§