Struct wayland_sys::client::WAYLAND_CLIENT_OPTION
source · pub struct WAYLAND_CLIENT_OPTION { /* private fields */ }
Methods from Deref<Target = Option<WaylandClient>>§
1.0.0 · sourcepub fn as_ref(&self) -> Option<&T>
pub fn as_ref(&self) -> Option<&T>
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:?}");
1.40.0 · sourcepub fn as_deref(&self) -> Option<&<T as Deref>::Target>where
T: Deref,
pub fn as_deref(&self) -> Option<&<T as Deref>::Target>where
T: Deref,
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);
1.0.0 · sourcepub fn iter(&self) -> Iter<'_, T>
pub fn iter(&self) -> Iter<'_, T>
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);
sourcepub fn contains<U>(&self, x: &U) -> boolwhere
U: PartialEq<T>,
🔬This is a nightly-only experimental API. (option_result_contains
)
pub fn contains<U>(&self, x: &U) -> boolwhere
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);
Trait Implementations§
source§impl Deref for WAYLAND_CLIENT_OPTION
impl Deref for WAYLAND_CLIENT_OPTION
§type Target = Option<WaylandClient>
type Target = Option<WaylandClient>
The resulting type after dereferencing.
source§fn deref(&self) -> &Option<WaylandClient>
fn deref(&self) -> &Option<WaylandClient>
Dereferences the value.