[−]Struct wayland_sys::egl::WAYLAND_EGL_OPTION
Methods from Deref<Target = Option<WaylandEgl>>
#[must_use]
pub fn is_some(&self) -> bool
1.0.0[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]
pub fn is_none(&self) -> bool
1.0.0[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);
pub fn as_ref(&self) -> Option<&T>
1.0.0[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<&'a Option<T>>) -> Option<Pin<&'a T>>
1.33.0[src]
Converts from Pin<&Option<T>>
to Option<Pin<&T>>
pub fn as_pin_mut(self: Pin<&'a mut Option<T>>) -> Option<Pin<&'a mut T>>
1.33.0[src]
Converts from Pin<&mut Option<T>>
to Option<Pin<&mut T>>
pub 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 deref(&self) -> Option<&<T as Deref>::Target>
[src]
🔬 This is a nightly-only experimental API. (inner_deref
)
newly added
Converts from &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
.
Trait Implementations
impl Deref for WAYLAND_EGL_OPTION
type Target = Option<WaylandEgl>
The resulting type after dereferencing.
fn deref(&self) -> &Option<WaylandEgl>
impl LazyStatic for WAYLAND_EGL_OPTION
fn initialize(lazy: &Self)
Auto Trait Implementations
impl Unpin for WAYLAND_EGL_OPTION
impl Sync for WAYLAND_EGL_OPTION
impl Send for WAYLAND_EGL_OPTION
impl UnwindSafe for WAYLAND_EGL_OPTION
impl RefUnwindSafe for WAYLAND_EGL_OPTION
Blanket Implementations
impl<T> From<T> for T
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impl<T, U> Into<U> for T where
U: From<T>,
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U: From<T>,
impl<T, U> TryFrom<U> for T where
U: Into<T>,
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U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
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impl<T, U> TryInto<U> for T where
U: TryFrom<T>,
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U: TryFrom<T>,
type Error = <U as TryFrom<T>>::Error
The type returned in the event of a conversion error.
fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>
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impl<T> Borrow<T> for T where
T: ?Sized,
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T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
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T: ?Sized,
fn borrow_mut(&mut self) -> &mut T
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impl<T> Any for T where
T: 'static + ?Sized,
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T: 'static + ?Sized,