31 lines
654 B
Rust
31 lines
654 B
Rust
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// A poly-fill for `lazy_cell`
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// Replace with std::sync::LazyLock when https://github.com/rust-lang/rust/issues/109736 is stablized.
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// This isn't used on every platform, which can come up as dead code warnings.
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#![allow(dead_code)]
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use std::ops::Deref;
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use std::sync::OnceLock;
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pub(crate) struct Lazy<T> {
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cell: OnceLock<T>,
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init: fn() -> T,
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}
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impl<T> Lazy<T> {
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pub const fn new(f: fn() -> T) -> Self {
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Self {
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cell: OnceLock::new(),
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init: f,
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}
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}
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}
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impl<T> Deref for Lazy<T> {
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type Target = T;
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#[inline]
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fn deref(&self) -> &'_ T {
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self.cell.get_or_init(self.init)
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}
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}
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