mirror of https://github.com/rust-lang/rust
24 lines
382 B
Rust
24 lines
382 B
Rust
//@ check-pass
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struct LazyLock<T> {
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data: (Option<T>, fn() -> T),
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}
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impl<T> LazyLock<T> {
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pub const fn new(f: fn() -> T) -> LazyLock<T> {
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LazyLock { data: (None, f) }
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}
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}
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struct A<T = i32>(Option<T>);
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impl<T> Default for A<T> {
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fn default() -> Self {
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A(None)
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}
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}
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static EMPTY_SET: LazyLock<A<i32>> = LazyLock::new(A::default);
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fn main() {}
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