15 lines
311 B
Rust
15 lines
311 B
Rust
#![feature(associated_type_defaults)]
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use std::ops::Index;
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trait Hierarchy {
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type Value;
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type ChildKey;
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type Children = dyn Index<Self::ChildKey, Output=dyn Hierarchy>;
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//~^ ERROR: the value of the associated types
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fn data(&self) -> Option<(Self::Value, Self::Children)>;
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}
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fn main() {}
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