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31 lines
875 B
Rust
31 lines
875 B
Rust
// run-pass
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#![allow(dead_code)]
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#![allow(unused_assignments)]
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// Issue #2263.
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// pretty-expanded FIXME #23616
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#![allow(unused_variables)]
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// Should pass region checking.
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fn ok(f: Box<dyn FnMut(&usize)>) {
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// Here, g is a function that can accept a usize pointer with
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// lifetime r, and f is a function that can accept a usize pointer
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// with any lifetime. The assignment g = f should be OK (i.e.,
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// f's type should be a subtype of g's type), because f can be
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// used in any context that expects g's type. But this currently
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// fails.
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let mut g: Box<dyn for<'r> FnMut(&'r usize)> = Box::new(|x| { });
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g = f;
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}
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// This version is the same as above, except that here, g's type is
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// inferred.
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fn ok_inferred(f: Box<dyn FnMut(&usize)>) {
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let mut g: Box<dyn for<'r> FnMut(&'r usize)> = Box::new(|_| {});
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g = f;
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}
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pub fn main() {
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}
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