Trait artifact_app::dev_prefix::AsRef 1.0.0
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[src]
pub trait AsRef<T> where
T: ?Sized, { fn as_ref(&self) -> &T; }
A cheap reference-to-reference conversion. Used to convert a value to a reference value within generic code.
AsRef is very similar to, but serves a slightly different purpose than,
Borrow.
AsRef is to be used when wishing to convert to a reference of another
type.
Borrow is more related to the notion of taking the reference. It is
useful when wishing to abstract over the type of reference
(&T, &mut T) or allow both the referenced and owned type to be treated
in the same manner.
The key difference between the two traits is the intention:
- Use
AsRefwhen goal is to simply convert into a reference - Use
Borrowwhen goal is related to writing code that is agnostic to the type of borrow and if is reference or value
See the book for a more detailed comparison.
Note: this trait must not fail. If the conversion can fail, use a
dedicated method which returns an Option<T> or a Result<T, E>.
Generic Implementations
AsRefauto-dereferences if the inner type is a reference or a mutable reference (e.g.:foo.as_ref()will work the same iffoohas type&mut Fooor&&mut Foo)
Examples
Both String and &str implement AsRef<str>:
fn is_hello<T: AsRef<str>>(s: T) { assert_eq!("hello", s.as_ref()); } let s = "hello"; is_hello(s); let s = "hello".to_string(); is_hello(s);
Required Methods
Trait Implementations
impl<T> Trait for AsRef<T> + 'static + Send where
T: ?Sized,
T: ?Sized,
impl<T> Trait for AsRef<T> + 'static + Sync where
T: ?Sized,
T: ?Sized,
impl<T> Trait for AsRef<T> + 'static + Sync + Send where
T: ?Sized,
T: ?Sized,
Implementations on Foreign Types
impl<A> AsRef<[<A as Array>::Item]> for SmallVec<A> where
A: Array,
A: Array,
impl<'a, T, U> AsRef<U> for &'a T where
T: AsRef<U> + ?Sized,
U: ?Sized, [src]
T: AsRef<U> + ?Sized,
U: ?Sized,
impl<T> AsRef<[T]> for [T; 3][src]
impl<T> AsRef<[T]> for [T; 27][src]
impl<T> AsRef<[T]> for [T][src]
impl AsRef<[u8]> for str[src]
impl<T> AsRef<[T]> for [T; 15][src]
impl<T> AsRef<[T]> for [T; 20][src]
impl<T> AsRef<[T]> for [T; 6][src]
impl<T> AsRef<[T]> for [T; 9][src]
impl<T> AsRef<[T]> for [T; 17][src]
impl<T> AsRef<[T]> for [T; 13][src]
impl<T> AsRef<[T]> for [T; 16][src]
impl<T> AsRef<[T]> for [T; 8][src]
impl<T> AsRef<[T]> for [T; 23][src]
impl<'a, T> AsRef<[T]> for Iter<'a, T>[src]
impl<T> AsRef<[T]> for [T; 12][src]
impl<T> AsRef<[T]> for [T; 26][src]
impl<T> AsRef<[T]> for [T; 21][src]
impl<T> AsRef<[T]> for [T; 1][src]
impl<'a, T, U> AsRef<U> for &'a mut T where
T: AsRef<U> + ?Sized,
U: ?Sized, [src]
T: AsRef<U> + ?Sized,
U: ?Sized,
impl<T> AsRef<[T]> for [T; 28][src]
impl<T> AsRef<[T]> for [T; 5][src]
impl<T> AsRef<[T]> for [T; 7][src]
impl<T> AsRef<[T]> for [T; 18][src]
impl<T> AsRef<[T]> for [T; 10][src]
impl<T> AsRef<[T]> for [T; 14][src]
impl<T> AsRef<[T]> for [T; 24][src]
impl<T> AsRef<[T]> for [T; 31][src]
impl<T> AsRef<[T]> for [T; 19][src]
impl<T> AsRef<[T]> for [T; 22][src]
impl<T> AsRef<[T]> for [T; 25][src]
impl<T> AsRef<[T]> for [T; 30][src]
impl<T> AsRef<[T]> for [T; 32][src]
impl<T> AsRef<[T]> for [T; 29][src]
impl AsRef<str> for str[src]
impl<T> AsRef<[T]> for [T; 2][src]
impl<T> AsRef<[T]> for [T; 11][src]
impl<T> AsRef<[T]> for [T; 4][src]
impl<T> AsRef<[T]> for [T; 0][src]
impl<S> AsRef<str> for UniCase<S> where
S: AsRef<str>,
S: AsRef<str>,
impl AsRef<Path> for TempDir[src]
impl<T> AsRef<[T]> for Vec<T>[src]
impl<'a, T> AsRef<T> for Cow<'a, T> where
T: ToOwned + ?Sized, [src]
T: ToOwned + ?Sized,
impl AsRef<[u8]> for String[src]
impl AsRef<str> for String[src]
impl<T> AsRef<Vec<T>> for Vec<T>[src]
impl<T> AsRef<T> for Rc<T> where
T: ?Sized, [src]
T: ?Sized,
impl<T> AsRef<T> for Box<T> where
T: ?Sized, [src]
T: ?Sized,
impl<S> AsRef<str> for UniCase<S> where
S: AsRef<str>,
S: AsRef<str>,
impl<S> AsRef<str> for Ascii<S> where
S: AsRef<str>,
S: AsRef<str>,
impl AsRef<[u8]> for BytesMut[src]
impl AsRef<[u8]> for Bytes[src]
impl<'a> AsRef<OsStr> for Iter<'a>[src]
impl AsRef<Path> for String[src]
impl AsRef<OsStr> for str[src]
impl<'a> AsRef<OsStr> for Components<'a>[src]
impl AsRef<Path> for OsStr[src]
impl AsRef<Path> for str[src]
impl AsRef<OsStr> for String[src]
impl AsRef<OsStr> for OsStr[src]
impl<'a> AsRef<Path> for Components<'a>[src]
impl AsRef<CStr> for CStr[src]
impl AsRef<CStr> for CString[src]
impl<'a> AsRef<Path> for Iter<'a>[src]
impl<'a> AsRef<Path> for Cow<'a, OsStr>[src]
impl<'a> AsRef<OsStr> for Component<'a>[src]
impl AsRef<str> for HttpVersion[src]
impl AsRef<str> for Method[src]
impl<L, R, Target> AsRef<Target> for Either<L, R> where
L: AsRef<Target>,
R: AsRef<Target>, [src]
L: AsRef<Target>,
R: AsRef<Target>,
impl AsRef<timeval> for TimeVal
impl AsRef<u32> for SigSet
impl AsRef<timespec> for TimeSpec
impl<T> AsRef<[u8]> for Window<T> where
T: AsRef<[u8]>, [src]
T: AsRef<[u8]>,
impl AsRef<[u8]> for Chunk[src]
impl AsRef<str> for Method[src]
impl AsRef<str> for Uri[src]
impl AsRef<[u8]> for Lit
impl AsRef<str> for Mime[src]
impl<'a> AsRef<str> for Name<'a>[src]
impl AsRef<str> for Url[src]
Return the serialization of this URL.