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Key

Struct Key 

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pub struct Key { /* private fields */ }
Expand description

The identity of something an application names, built from any hashable value.

A key carries the value’s type as well as its hash, so keys built from equal values of the same type are equal and keys of different types never are. An application’s own enums are therefore its natural keys, and one name cannot collide with another concern’s.

use urushi::Key;

#[derive(Hash)]
enum Pane {
    Preview,
    Chart,
}

assert_eq!(Key::of(&Pane::Preview), Key::of(&Pane::Preview));
assert_ne!(Key::of(&Pane::Preview), Key::of(&Pane::Chart));
assert_eq!(Key::from("preview"), Key::of(&"preview"));
assert_eq!(format!("{:?}", Key::from("preview")), "Key(preview)");

The value itself is not kept: a key is a type and a hash, which is what lets it name anything without owning it. Two distinct values of one type whose hashes collide are therefore one key, as they are in any hash map.

What it does keep is a label to print, and only one that costs nothing to hold: the literal for a key built from one, and the type’s name otherwise. A key stays Copy, and a log line says which key rather than which hash.

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impl Key

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pub fn of<T: Hash + 'static>(value: &T) -> Self

Builds the key of value.

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impl Clone for Key

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fn clone(&self) -> Key

Returns a duplicate of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for Key

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fn fmt(&self, formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl From<&'static str> for Key

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fn from(name: &'static str) -> Self

Converts to this type from the input type.
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impl Hash for Key

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fn hash<H: Hasher>(&self, hasher: &mut H)

Feeds this value into the given Hasher. Read more
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fn hash_slice<H>(data: &[Self], state: &mut H)
where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher. Read more
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impl PartialEq for Key

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fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.
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fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl Copy for Key

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impl Eq for Key

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impl Freeze for Key

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impl RefUnwindSafe for Key

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impl Send for Key

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impl Sync for Key

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impl Unpin for Key

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impl UnsafeUnpin for Key

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impl UnwindSafe for Key

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.