45 lines
1.0 KiB
Rust
45 lines
1.0 KiB
Rust
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#![feature(generators, generator_trait)]
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use std::{
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ops::{Generator, GeneratorState},
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pin::Pin,
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};
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fn firstn() -> impl Generator<Yield = u64, Return = ()> {
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static move || {
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let mut num = 0;
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let num = &mut num;
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yield *num;
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*num += 1; //~ ERROR dangling pointer was dereferenced
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}
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}
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struct GeneratorIteratorAdapter<G>(G);
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impl<G> Iterator for GeneratorIteratorAdapter<G>
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where
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G: Generator<Return = ()>,
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{
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type Item = G::Yield;
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fn next(&mut self) -> Option<Self::Item> {
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let me = unsafe { Pin::new_unchecked(&mut self.0) };
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match me.resume() {
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GeneratorState::Yielded(x) => Some(x),
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GeneratorState::Complete(_) => None,
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}
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}
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}
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fn main() {
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let mut generator_iterator_2 = {
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let mut generator_iterator = GeneratorIteratorAdapter(firstn());
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generator_iterator.next(); // pin it
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generator_iterator // move it
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}; // *deallocate* generator_iterator
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generator_iterator_2.next(); // and use moved value
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}
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