pub struct TimeDate { /* private fields */ }Expand description
Date in the proleptic Gregorian calendar.
By default, years between ±9999 inclusive are representable. This can be expanded to ±999,999
inclusive by enabling the large-dates crate feature. Doing so has performance implications
and introduces some ambiguities when parsing.
Implementations
sourceimpl Date
impl Date
sourcepub const MIN: Date = Self::__from_ordinal_date_unchecked(MIN_YEAR, 1)
pub const MIN: Date = Self::__from_ordinal_date_unchecked(MIN_YEAR, 1)
The minimum valid Date.
The value of this may vary depending on the feature flags enabled.
sourcepub const MAX: Date = Self::__from_ordinal_date_unchecked(MAX_YEAR, days_in_year(MAX_YEAR))
pub const MAX: Date = Self::__from_ordinal_date_unchecked(MAX_YEAR, days_in_year(MAX_YEAR))
The maximum valid Date.
The value of this may vary depending on the feature flags enabled.
sourcepub const fn from_calendar_date(
year: i32,
month: Month,
day: u8
) -> Result<Date, ComponentRange>
pub const fn from_calendar_date(
year: i32,
month: Month,
day: u8
) -> Result<Date, ComponentRange>
Attempt to create a Date from the year, month, and day.
assert!(Date::from_calendar_date(2019, Month::January, 1).is_ok());
assert!(Date::from_calendar_date(2019, Month::December, 31).is_ok());assert!(Date::from_calendar_date(2019, Month::February, 29).is_err()); // 2019 isn't a leap year.sourcepub const fn from_ordinal_date(
year: i32,
ordinal: u16
) -> Result<Date, ComponentRange>
pub const fn from_ordinal_date(
year: i32,
ordinal: u16
) -> Result<Date, ComponentRange>
Attempt to create a Date from the year and ordinal day number.
assert!(Date::from_ordinal_date(2019, 1).is_ok());
assert!(Date::from_ordinal_date(2019, 365).is_ok());assert!(Date::from_ordinal_date(2019, 366).is_err()); // 2019 isn't a leap year.sourcepub const fn from_iso_week_date(
year: i32,
week: u8,
weekday: Weekday
) -> Result<Date, ComponentRange>
pub const fn from_iso_week_date(
year: i32,
week: u8,
weekday: Weekday
) -> Result<Date, ComponentRange>
Attempt to create a Date from the ISO year, week, and weekday.
assert!(Date::from_iso_week_date(2019, 1, Monday).is_ok());
assert!(Date::from_iso_week_date(2019, 1, Tuesday).is_ok());
assert!(Date::from_iso_week_date(2020, 53, Friday).is_ok());assert!(Date::from_iso_week_date(2019, 53, Monday).is_err()); // 2019 doesn't have 53 weeks.sourcepub const fn from_julian_day(julian_day: i32) -> Result<Date, ComponentRange>
pub const fn from_julian_day(julian_day: i32) -> Result<Date, ComponentRange>
Create a Date from the Julian day.
The algorithm to perform this conversion is derived from one provided by Peter Baum; it is freely available here.
assert_eq!(Date::from_julian_day(0), Ok(date!(-4713 - 11 - 24)));
assert_eq!(Date::from_julian_day(2_451_545), Ok(date!(2000 - 01 - 01)));
assert_eq!(Date::from_julian_day(2_458_485), Ok(date!(2019 - 01 - 01)));
assert_eq!(Date::from_julian_day(2_458_849), Ok(date!(2019 - 12 - 31)));sourcepub const fn year(self) -> i32
pub const fn year(self) -> i32
Get the year of the date.
assert_eq!(date!(2019 - 01 - 01).year(), 2019);
assert_eq!(date!(2019 - 12 - 31).year(), 2019);
assert_eq!(date!(2020 - 01 - 01).year(), 2020);sourcepub const fn month(self) -> Month
pub const fn month(self) -> Month
Get the month.
assert_eq!(date!(2019 - 01 - 01).month(), Month::January);
assert_eq!(date!(2019 - 12 - 31).month(), Month::December);sourcepub const fn day(self) -> u8
pub const fn day(self) -> u8
Get the day of the month.
The returned value will always be in the range 1..=31.
assert_eq!(date!(2019 - 01 - 01).day(), 1);
assert_eq!(date!(2019 - 12 - 31).day(), 31);sourcepub const fn ordinal(self) -> u16
pub const fn ordinal(self) -> u16
Get the day of the year.
The returned value will always be in the range 1..=366 (1..=365 for common years).
assert_eq!(date!(2019 - 01 - 01).ordinal(), 1);
assert_eq!(date!(2019 - 12 - 31).ordinal(), 365);sourcepub const fn iso_week(self) -> u8
pub const fn iso_week(self) -> u8
Get the ISO week number.
The returned value will always be in the range 1..=53.
assert_eq!(date!(2019 - 01 - 01).iso_week(), 1);
assert_eq!(date!(2019 - 10 - 04).iso_week(), 40);
assert_eq!(date!(2020 - 01 - 01).iso_week(), 1);
assert_eq!(date!(2020 - 12 - 31).iso_week(), 53);
assert_eq!(date!(2021 - 01 - 01).iso_week(), 53);sourcepub const fn sunday_based_week(self) -> u8
pub const fn sunday_based_week(self) -> u8
Get the week number where week 1 begins on the first Sunday.
The returned value will always be in the range 0..=53.
assert_eq!(date!(2019 - 01 - 01).sunday_based_week(), 0);
assert_eq!(date!(2020 - 01 - 01).sunday_based_week(), 0);
assert_eq!(date!(2020 - 12 - 31).sunday_based_week(), 52);
assert_eq!(date!(2021 - 01 - 01).sunday_based_week(), 0);sourcepub const fn monday_based_week(self) -> u8
pub const fn monday_based_week(self) -> u8
Get the week number where week 1 begins on the first Monday.
The returned value will always be in the range 0..=53.
assert_eq!(date!(2019 - 01 - 01).monday_based_week(), 0);
assert_eq!(date!(2020 - 01 - 01).monday_based_week(), 0);
assert_eq!(date!(2020 - 12 - 31).monday_based_week(), 52);
assert_eq!(date!(2021 - 01 - 01).monday_based_week(), 0);sourcepub const fn to_calendar_date(self) -> (i32, Month, u8)
pub const fn to_calendar_date(self) -> (i32, Month, u8)
Get the year, month, and day.
assert_eq!(
date!(2019 - 01 - 01).to_calendar_date(),
(2019, Month::January, 1)
);sourcepub const fn to_ordinal_date(self) -> (i32, u16)
pub const fn to_ordinal_date(self) -> (i32, u16)
Get the year and ordinal day number.
assert_eq!(date!(2019 - 01 - 01).to_ordinal_date(), (2019, 1));sourcepub const fn to_iso_week_date(self) -> (i32, u8, Weekday)
pub const fn to_iso_week_date(self) -> (i32, u8, Weekday)
Get the ISO 8601 year, week number, and weekday.
assert_eq!(date!(2019 - 01 - 01).to_iso_week_date(), (2019, 1, Tuesday));
assert_eq!(date!(2019 - 10 - 04).to_iso_week_date(), (2019, 40, Friday));
assert_eq!(
date!(2020 - 01 - 01).to_iso_week_date(),
(2020, 1, Wednesday)
);
assert_eq!(
date!(2020 - 12 - 31).to_iso_week_date(),
(2020, 53, Thursday)
);
assert_eq!(date!(2021 - 01 - 01).to_iso_week_date(), (2020, 53, Friday));sourcepub const fn weekday(self) -> Weekday
pub const fn weekday(self) -> Weekday
Get the weekday.
assert_eq!(date!(2019 - 01 - 01).weekday(), Tuesday);
assert_eq!(date!(2019 - 02 - 01).weekday(), Friday);
assert_eq!(date!(2019 - 03 - 01).weekday(), Friday);
assert_eq!(date!(2019 - 04 - 01).weekday(), Monday);
assert_eq!(date!(2019 - 05 - 01).weekday(), Wednesday);
assert_eq!(date!(2019 - 06 - 01).weekday(), Saturday);
assert_eq!(date!(2019 - 07 - 01).weekday(), Monday);
assert_eq!(date!(2019 - 08 - 01).weekday(), Thursday);
assert_eq!(date!(2019 - 09 - 01).weekday(), Sunday);
assert_eq!(date!(2019 - 10 - 01).weekday(), Tuesday);
assert_eq!(date!(2019 - 11 - 01).weekday(), Friday);
assert_eq!(date!(2019 - 12 - 01).weekday(), Sunday);sourcepub const fn next_day(self) -> Option<Date>
pub const fn next_day(self) -> Option<Date>
Get the next calendar date.
assert_eq!(
date!(2019 - 01 - 01).next_day(),
Some(date!(2019 - 01 - 02))
);
assert_eq!(
date!(2019 - 01 - 31).next_day(),
Some(date!(2019 - 02 - 01))
);
assert_eq!(
date!(2019 - 12 - 31).next_day(),
Some(date!(2020 - 01 - 01))
);
assert_eq!(Date::MAX.next_day(), None);sourcepub const fn previous_day(self) -> Option<Date>
pub const fn previous_day(self) -> Option<Date>
Get the previous calendar date.
assert_eq!(
date!(2019 - 01 - 02).previous_day(),
Some(date!(2019 - 01 - 01))
);
assert_eq!(
date!(2019 - 02 - 01).previous_day(),
Some(date!(2019 - 01 - 31))
);
assert_eq!(
date!(2020 - 01 - 01).previous_day(),
Some(date!(2019 - 12 - 31))
);
assert_eq!(Date::MIN.previous_day(), None);sourcepub const fn to_julian_day(self) -> i32
pub const fn to_julian_day(self) -> i32
Get the Julian day for the date.
The algorithm to perform this conversion is derived from one provided by Peter Baum; it is freely available here.
assert_eq!(date!(-4713 - 11 - 24).to_julian_day(), 0);
assert_eq!(date!(2000 - 01 - 01).to_julian_day(), 2_451_545);
assert_eq!(date!(2019 - 01 - 01).to_julian_day(), 2_458_485);
assert_eq!(date!(2019 - 12 - 31).to_julian_day(), 2_458_849);sourcepub const fn checked_add(self, duration: Duration) -> Option<Date>
pub const fn checked_add(self, duration: Duration) -> Option<Date>
Computes self + duration, returning None if an overflow occurred.
assert_eq!(Date::MAX.checked_add(1.days()), None);
assert_eq!(Date::MIN.checked_add((-2).days()), None);
assert_eq!(
date!(2020 - 12 - 31).checked_add(2.days()),
Some(date!(2021 - 01 - 02))
);Note
This function only takes whole days into account.
assert_eq!(Date::MAX.checked_add(23.hours()), Some(Date::MAX));
assert_eq!(Date::MIN.checked_add((-23).hours()), Some(Date::MIN));
assert_eq!(
date!(2020 - 12 - 31).checked_add(23.hours()),
Some(date!(2020 - 12 - 31))
);
assert_eq!(
date!(2020 - 12 - 31).checked_add(47.hours()),
Some(date!(2021 - 01 - 01))
);sourcepub const fn checked_sub(self, duration: Duration) -> Option<Date>
pub const fn checked_sub(self, duration: Duration) -> Option<Date>
Computes self - duration, returning None if an overflow occurred.
assert_eq!(Date::MAX.checked_sub((-2).days()), None);
assert_eq!(Date::MIN.checked_sub(1.days()), None);
assert_eq!(
date!(2020 - 12 - 31).checked_sub(2.days()),
Some(date!(2020 - 12 - 29))
);Note
This function only takes whole days into account.
assert_eq!(Date::MAX.checked_sub((-23).hours()), Some(Date::MAX));
assert_eq!(Date::MIN.checked_sub(23.hours()), Some(Date::MIN));
assert_eq!(
date!(2020 - 12 - 31).checked_sub(23.hours()),
Some(date!(2020 - 12 - 31))
);
assert_eq!(
date!(2020 - 12 - 31).checked_sub(47.hours()),
Some(date!(2020 - 12 - 30))
);sourcepub const fn saturating_add(self, duration: Duration) -> Date
pub const fn saturating_add(self, duration: Duration) -> Date
Computes self + duration, saturating value on overflow.
assert_eq!(Date::MAX.saturating_add(1.days()), Date::MAX);
assert_eq!(Date::MIN.saturating_add((-2).days()), Date::MIN);
assert_eq!(
date!(2020 - 12 - 31).saturating_add(2.days()),
date!(2021 - 01 - 02)
);Note
This function only takes whole days into account.
assert_eq!(
date!(2020 - 12 - 31).saturating_add(23.hours()),
date!(2020 - 12 - 31)
);
assert_eq!(
date!(2020 - 12 - 31).saturating_add(47.hours()),
date!(2021 - 01 - 01)
);sourcepub const fn saturating_sub(self, duration: Duration) -> Date
pub const fn saturating_sub(self, duration: Duration) -> Date
Computes self - duration, saturating value on overflow.
assert_eq!(Date::MAX.saturating_sub((-2).days()), Date::MAX);
assert_eq!(Date::MIN.saturating_sub(1.days()), Date::MIN);
assert_eq!(
date!(2020 - 12 - 31).saturating_sub(2.days()),
date!(2020 - 12 - 29)
);Note
This function only takes whole days into account.
assert_eq!(
date!(2020 - 12 - 31).saturating_sub(23.hours()),
date!(2020 - 12 - 31)
);
assert_eq!(
date!(2020 - 12 - 31).saturating_sub(47.hours()),
date!(2020 - 12 - 30)
);sourcepub const fn replace_year(self, year: i32) -> Result<Date, ComponentRange>
pub const fn replace_year(self, year: i32) -> Result<Date, ComponentRange>
Replace the year. The month and day will be unchanged.
assert_eq!(
date!(2022 - 02 - 18).replace_year(2019),
Ok(date!(2019 - 02 - 18))
);
assert!(date!(2022 - 02 - 18).replace_year(-1_000_000_000).is_err()); // -1_000_000_000 isn't a valid year
assert!(date!(2022 - 02 - 18).replace_year(1_000_000_000).is_err()); // 1_000_000_000 isn't a valid yearsourcepub const fn replace_month(self, month: Month) -> Result<Date, ComponentRange>
pub const fn replace_month(self, month: Month) -> Result<Date, ComponentRange>
Replace the month of the year.
assert_eq!(
date!(2022 - 02 - 18).replace_month(Month::January),
Ok(date!(2022 - 01 - 18))
);
assert!(
date!(2022 - 01 - 30)
.replace_month(Month::February)
.is_err()
); // 30 isn't a valid day in Februarysourcepub const fn replace_day(self, day: u8) -> Result<Date, ComponentRange>
pub const fn replace_day(self, day: u8) -> Result<Date, ComponentRange>
Replace the day of the month.
assert_eq!(
date!(2022 - 02 - 18).replace_day(1),
Ok(date!(2022 - 02 - 01))
);
assert!(date!(2022 - 02 - 18).replace_day(0).is_err()); // 0 isn't a valid day
assert!(date!(2022 - 02 - 18).replace_day(30).is_err()); // 30 isn't a valid day in Februarysourceimpl Date
impl Date
Methods to add a Time component, resulting in a PrimitiveDateTime.
sourcepub const fn midnight(self) -> PrimitiveDateTime
pub const fn midnight(self) -> PrimitiveDateTime
Create a PrimitiveDateTime using the existing date. The Time component will be set
to midnight.
assert_eq!(date!(1970-01-01).midnight(), datetime!(1970-01-01 0:00));sourcepub const fn with_time(self, time: Time) -> PrimitiveDateTime
pub const fn with_time(self, time: Time) -> PrimitiveDateTime
Create a PrimitiveDateTime using the existing date and the provided Time.
assert_eq!(
date!(1970-01-01).with_time(time!(0:00)),
datetime!(1970-01-01 0:00),
);sourcepub const fn with_hms(
self,
hour: u8,
minute: u8,
second: u8
) -> Result<PrimitiveDateTime, ComponentRange>
pub const fn with_hms(
self,
hour: u8,
minute: u8,
second: u8
) -> Result<PrimitiveDateTime, ComponentRange>
Attempt to create a PrimitiveDateTime using the existing date and the provided time.
assert!(date!(1970 - 01 - 01).with_hms(0, 0, 0).is_ok());
assert!(date!(1970 - 01 - 01).with_hms(24, 0, 0).is_err());sourcepub const fn with_hms_milli(
self,
hour: u8,
minute: u8,
second: u8,
millisecond: u16
) -> Result<PrimitiveDateTime, ComponentRange>
pub const fn with_hms_milli(
self,
hour: u8,
minute: u8,
second: u8,
millisecond: u16
) -> Result<PrimitiveDateTime, ComponentRange>
Attempt to create a PrimitiveDateTime using the existing date and the provided time.
assert!(date!(1970 - 01 - 01).with_hms_milli(0, 0, 0, 0).is_ok());
assert!(date!(1970 - 01 - 01).with_hms_milli(24, 0, 0, 0).is_err());sourcepub const fn with_hms_micro(
self,
hour: u8,
minute: u8,
second: u8,
microsecond: u32
) -> Result<PrimitiveDateTime, ComponentRange>
pub const fn with_hms_micro(
self,
hour: u8,
minute: u8,
second: u8,
microsecond: u32
) -> Result<PrimitiveDateTime, ComponentRange>
Attempt to create a PrimitiveDateTime using the existing date and the provided time.
assert!(date!(1970 - 01 - 01).with_hms_micro(0, 0, 0, 0).is_ok());
assert!(date!(1970 - 01 - 01).with_hms_micro(24, 0, 0, 0).is_err());sourcepub const fn with_hms_nano(
self,
hour: u8,
minute: u8,
second: u8,
nanosecond: u32
) -> Result<PrimitiveDateTime, ComponentRange>
pub const fn with_hms_nano(
self,
hour: u8,
minute: u8,
second: u8,
nanosecond: u32
) -> Result<PrimitiveDateTime, ComponentRange>
Attempt to create a PrimitiveDateTime using the existing date and the provided time.
assert!(date!(1970 - 01 - 01).with_hms_nano(0, 0, 0, 0).is_ok());
assert!(date!(1970 - 01 - 01).with_hms_nano(24, 0, 0, 0).is_err());sourceimpl Date
impl Date
sourcepub fn format_into(
self,
output: &mut impl Write,
format: &impl Formattable
) -> Result<usize, Format>
pub fn format_into(
self,
output: &mut impl Write,
format: &impl Formattable
) -> Result<usize, Format>
Format the Date using the provided format description.
sourcepub fn format(self, format: &impl Formattable) -> Result<String, Format>
pub fn format(self, format: &impl Formattable) -> Result<String, Format>
Format the Date using the provided format description.
let format = format_description::parse("[year]-[month]-[day]")?;
assert_eq!(date!(2020 - 01 - 02).format(&format)?, "2020-01-02");Trait Implementations
sourceimpl AddAssign<Duration> for Date
impl AddAssign<Duration> for Date
sourcefn add_assign(&mut self, rhs: Duration)
fn add_assign(&mut self, rhs: Duration)
+= operation. Read moresourceimpl AddAssign<Duration> for Date
impl AddAssign<Duration> for Date
sourcefn add_assign(&mut self, rhs: Duration)
fn add_assign(&mut self, rhs: Duration)
+= operation. Read moreimpl<'r> Decode<'r, MySql> for Date
impl<'r> Decode<'r, MySql> for Date
impl<'r> Decode<'r, Postgres> for Date
impl<'r> Decode<'r, Postgres> for Date
impl<'r> Decode<'r, Sqlite> for Date
impl<'r> Decode<'r, Sqlite> for Date
sourceimpl<'a> Deserialize<'a> for Date
impl<'a> Deserialize<'a> for Date
sourcefn deserialize<D>(
deserializer: D
) -> Result<Date, <D as Deserializer<'a>>::Error>where
D: Deserializer<'a>,
fn deserialize<D>(
deserializer: D
) -> Result<Date, <D as Deserializer<'a>>::Error>where
D: Deserializer<'a>,
impl Encode<'_, MySql> for Date
impl Encode<'_, MySql> for Date
impl Encode<'_, Postgres> for Date
impl Encode<'_, Postgres> for Date
impl Encode<'_, Sqlite> for Date
impl Encode<'_, Sqlite> for Date
fn encode_by_ref(&self, buf: &mut Vec<SqliteArgumentValue<'_>, Global>) -> IsNull
fn encode_by_ref(&self, buf: &mut Vec<SqliteArgumentValue<'_>, Global>) -> IsNull
fn encode(self, buf: &mut <DB as HasArguments<'q>>::ArgumentBuffer) -> IsNull
fn encode(self, buf: &mut <DB as HasArguments<'q>>::ArgumentBuffer) -> IsNull
self into buf in the expected format for the database.fn produces(&self) -> Option<<DB as Database>::TypeInfo>
fn size_hint(&self) -> usize
sourceimpl IntoActiveValue<Date> for TimeDate
impl IntoActiveValue<Date> for TimeDate
sourcefn into_active_value(self) -> ActiveValue<TimeDate>
fn into_active_value(self) -> ActiveValue<TimeDate>
sourceimpl Ord for Date
impl Ord for Date
1.21.0 · sourceconst fn max(self, other: Self) -> Self
const fn max(self, other: Self) -> Self
1.21.0 · sourceconst fn min(self, other: Self) -> Self
const fn min(self, other: Self) -> Self
1.50.0 · sourceconst fn clamp(self, min: Self, max: Self) -> Selfwhere
Self: PartialOrd<Self>,
const fn clamp(self, min: Self, max: Self) -> Selfwhere
Self: PartialOrd<Self>,
sourceimpl PartialOrd<Date> for Date
impl PartialOrd<Date> for Date
sourcefn partial_cmp(&self, other: &Date) -> Option<Ordering>
fn partial_cmp(&self, other: &Date) -> Option<Ordering>
1.0.0 · sourceconst fn le(&self, other: &Rhs) -> bool
const fn le(&self, other: &Rhs) -> bool
self and other) and is used by the <=
operator. Read moreimpl PgHasArrayType for Date
impl PgHasArrayType for Date
fn array_type_info() -> PgTypeInfo
fn array_compatible(ty: &PgTypeInfo) -> bool
sourceimpl Serialize for Date
impl Serialize for Date
sourcefn serialize<S>(
&self,
serializer: S
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
fn serialize<S>(
&self,
serializer: S
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
sourceimpl SubAssign<Duration> for Date
impl SubAssign<Duration> for Date
sourcefn sub_assign(&mut self, rhs: Duration)
fn sub_assign(&mut self, rhs: Duration)
-= operation. Read moresourceimpl SubAssign<Duration> for Date
impl SubAssign<Duration> for Date
sourcefn sub_assign(&mut self, rhs: Duration)
fn sub_assign(&mut self, rhs: Duration)
-= operation. Read moresourceimpl TryFromU64 for Date
impl TryFromU64 for Date
sourcefn try_from_u64(_: u64) -> Result<Self, DbErr>
fn try_from_u64(_: u64) -> Result<Self, DbErr>
sourceimpl TryGetable for Date
impl TryGetable for Date
sourcefn try_get(res: &QueryResult, pre: &str, col: &str) -> Result<Self, TryGetError>
fn try_get(res: &QueryResult, pre: &str, col: &str) -> Result<Self, TryGetError>
impl Type<MySql> for Date
impl Type<MySql> for Date
fn compatible(ty: &<DB as Database>::TypeInfo) -> bool
fn compatible(ty: &<DB as Database>::TypeInfo) -> bool
impl Type<Postgres> for Date
impl Type<Postgres> for Date
fn compatible(ty: &<DB as Database>::TypeInfo) -> bool
fn compatible(ty: &<DB as Database>::TypeInfo) -> bool
impl Type<Sqlite> for Date
impl Type<Sqlite> for Date
fn compatible(ty: &SqliteTypeInfo) -> bool
fn compatible(ty: &SqliteTypeInfo) -> bool
impl Copy for Date
impl Eq for Date
impl StructuralEq for Date
impl StructuralPartialEq for Date
Auto Trait Implementations
impl RefUnwindSafe for Date
impl Send for Date
impl Sync for Date
impl Unpin for Date
impl UnwindSafe for Date
Blanket Implementations
sourceimpl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
sourceimpl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
sourcefn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key and return true if they are equal.