65 lines
1.9 KiB
Rust
65 lines
1.9 KiB
Rust
use crate::borrow::Cow;
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use super::Vec;
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#[stable(feature = "cow_from_vec", since = "1.8.0")]
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impl<'a, T: Clone> From<&'a [T]> for Cow<'a, [T]> {
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/// Creates a [`Borrowed`] variant of [`Cow`]
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/// from a slice.
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///
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/// This conversion does not allocate or clone the data.
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///
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/// [`Borrowed`]: crate::borrow::Cow::Borrowed
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fn from(s: &'a [T]) -> Cow<'a, [T]> {
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Cow::Borrowed(s)
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}
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}
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#[stable(feature = "cow_from_array_ref", since = "1.77.0")]
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impl<'a, T: Clone, const N: usize> From<&'a [T; N]> for Cow<'a, [T]> {
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/// Creates a [`Borrowed`] variant of [`Cow`]
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/// from a reference to an array.
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///
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/// This conversion does not allocate or clone the data.
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///
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/// [`Borrowed`]: crate::borrow::Cow::Borrowed
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fn from(s: &'a [T; N]) -> Cow<'a, [T]> {
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Cow::Borrowed(s as &[_])
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}
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}
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#[stable(feature = "cow_from_vec", since = "1.8.0")]
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impl<'a, T: Clone> From<Vec<T>> for Cow<'a, [T]> {
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/// Creates an [`Owned`] variant of [`Cow`]
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/// from an owned instance of [`Vec`].
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///
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/// This conversion does not allocate or clone the data.
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///
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/// [`Owned`]: crate::borrow::Cow::Owned
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fn from(v: Vec<T>) -> Cow<'a, [T]> {
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Cow::Owned(v)
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}
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}
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#[stable(feature = "cow_from_vec_ref", since = "1.28.0")]
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impl<'a, T: Clone> From<&'a Vec<T>> for Cow<'a, [T]> {
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/// Creates a [`Borrowed`] variant of [`Cow`]
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/// from a reference to [`Vec`].
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///
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/// This conversion does not allocate or clone the data.
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///
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/// [`Borrowed`]: crate::borrow::Cow::Borrowed
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fn from(v: &'a Vec<T>) -> Cow<'a, [T]> {
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Cow::Borrowed(v.as_slice())
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}
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}
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#[stable(feature = "rust1", since = "1.0.0")]
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impl<'a, T> FromIterator<T> for Cow<'a, [T]>
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where
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T: Clone,
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{
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fn from_iter<I: IntoIterator<Item = T>>(it: I) -> Cow<'a, [T]> {
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Cow::Owned(FromIterator::from_iter(it))
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}
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}
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