mirror of https://github.com/rust-lang/rust
41 lines
966 B
Rust
41 lines
966 B
Rust
// Test a case where we setup relationships like `'x: 'a` or `'a: 'x`,
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// where `'x` is bound in closure type but `'a` is free. This forces
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// us to approximate `'x` one way or the other.
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//@ compile-flags:-Zverbose-internals
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#![feature(rustc_attrs)]
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use std::cell::Cell;
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fn foo<'a, F>(_cell: Cell<&'a u32>, _f: F)
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where
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F: for<'x> FnOnce(Cell<&'a u32>, Cell<&'x u32>),
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{
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}
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#[rustc_regions]
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fn case1() {
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let a = 0;
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let cell = Cell::new(&a);
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foo(cell, |cell_a, cell_x| {
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cell_a.set(cell_x.get()); // forces 'x: 'a, error in closure
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//~^ ERROR
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})
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}
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#[rustc_regions]
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fn case2() {
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let a = 0;
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let cell = Cell::new(&a);
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//~^ ERROR `a` does not live long enough
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// As you can see in the stderr output, this closure propoagates a
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// requirement that `'a: 'static'.
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foo(cell, |cell_a, cell_x| {
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cell_x.set(cell_a.get()); // forces 'a: 'x, implies 'a = 'static -> borrow error
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})
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}
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fn main() { }
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