Struct tikv_util::metrics::process_linux::BOOT_TIME [−][src]
Fields
__private_field: ()
Methods from Deref<Target = Option<f64>>
#[must_use =
"if you intended to assert that this has a value, consider `.unwrap()` instead"]pub const fn is_some(&self) -> bool
1.0.0 (const: 1.48.0)[src]
Returns true
if the option is a Some
value.
Examples
let x: Option<u32> = Some(2); assert_eq!(x.is_some(), true); let x: Option<u32> = None; assert_eq!(x.is_some(), false);
#[must_use =
"if you intended to assert that this doesn't have a value, consider \
`.and_then(|| panic!(\"`Option` had a value when expected `None`\"))` instead"]pub const fn is_none(&self) -> bool
1.0.0 (const: 1.48.0)[src]
Returns true
if the option is a None
value.
Examples
let x: Option<u32> = Some(2); assert_eq!(x.is_none(), false); let x: Option<u32> = None; assert_eq!(x.is_none(), true);
#[must_use]pub fn contains<U>(&self, x: &U) -> bool where
U: PartialEq<T>,
[src]
U: PartialEq<T>,
option_result_contains
)Returns true
if the option is a Some
value containing the given value.
Examples
#![feature(option_result_contains)] let x: Option<u32> = Some(2); assert_eq!(x.contains(&2), true); let x: Option<u32> = Some(3); assert_eq!(x.contains(&2), false); let x: Option<u32> = None; assert_eq!(x.contains(&2), false);
pub const fn as_ref(&self) -> Option<&T>
1.0.0 (const: 1.48.0)[src]
Converts from &Option<T>
to Option<&T>
.
Examples
Converts an Option<
String
>
into an Option<
usize
>
, preserving the original.
The map
method takes the self
argument by value, consuming the original,
so this technique uses as_ref
to first take an Option
to a reference
to the value inside the original.
let text: Option<String> = Some("Hello, world!".to_string()); // First, cast `Option<String>` to `Option<&String>` with `as_ref`, // then consume *that* with `map`, leaving `text` on the stack. let text_length: Option<usize> = text.as_ref().map(|s| s.len()); println!("still can print text: {:?}", text);
pub fn as_pin_ref(self: Pin<&Option<T>>) -> Option<Pin<&T>>
1.33.0[src]
pub fn as_pin_mut(self: Pin<&mut Option<T>>) -> Option<Pin<&mut T>>
1.33.0[src]
pub const fn iter(&self) -> Iter<'_, T>
1.0.0[src]
Returns an iterator over the possibly contained value.
Examples
let x = Some(4); assert_eq!(x.iter().next(), Some(&4)); let x: Option<u32> = None; assert_eq!(x.iter().next(), None);
pub fn as_deref(&self) -> Option<&<T as Deref>::Target>
1.40.0[src]
Converts from Option<T>
(or &Option<T>
) to Option<&T::Target>
.
Leaves the original Option in-place, creating a new one with a reference
to the original one, additionally coercing the contents via Deref
.
Examples
let x: Option<String> = Some("hey".to_owned()); assert_eq!(x.as_deref(), Some("hey")); let x: Option<String> = None; assert_eq!(x.as_deref(), None);
Trait Implementations
impl Deref for BOOT_TIME
[src]
type Target = Option<f64>
The resulting type after dereferencing.
fn deref(&self) -> &Option<f64>
[src]
impl LazyStatic for BOOT_TIME
[src]
fn initialize(lazy: &Self)
[src]
Auto Trait Implementations
impl RefUnwindSafe for BOOT_TIME
impl Send for BOOT_TIME
impl Sync for BOOT_TIME
impl Unpin for BOOT_TIME
impl UnwindSafe for BOOT_TIME
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized,
[src]
T: 'static + ?Sized,
impl<T> Borrow<T> for T where
T: ?Sized,
[src]
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
[src]
T: ?Sized,
pub fn borrow_mut(&mut self) -> &mut T
[src]
impl<T> From<T> for T
[src]
impl<T> Instrument for T
[src]
pub fn instrument(self, span: Span) -> Instrumented<Self>
[src]
pub fn in_current_span(self) -> Instrumented<Self>
[src]
impl<T, U> Into<U> for T where
U: From<T>,
[src]
U: From<T>,
impl<T> Pointable for T
[src]
pub const ALIGN: usize
[src]
type Init = T
The type for initializers.
pub unsafe fn init(init: <T as Pointable>::Init) -> usize
[src]
pub unsafe fn deref<'a>(ptr: usize) -> &'a T
[src]
pub unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T
[src]
pub unsafe fn drop(ptr: usize)
[src]
impl<T> Same<T> for T
[src]
type Output = T
Should always be Self
impl<T> Sealed<T> for T where
T: ?Sized,
[src]
T: ?Sized,
impl<T> SendSyncUnwindSafe for T where
T: Send + Sync + UnwindSafe + ?Sized,
[src]
T: Send + Sync + UnwindSafe + ?Sized,
impl<T, U> TryFrom<U> for T where
U: Into<T>,
[src]
U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
[src]
impl<T, U> TryInto<U> for T where
U: TryFrom<T>,
[src]
U: TryFrom<T>,
type Error = <U as TryFrom<T>>::Error
The type returned in the event of a conversion error.
pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>
[src]
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
[src]
V: MultiLane<T>,