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A comment on Abstraction without overhead: traits in Rust. Parent comment

Re:Abstraction without overhead: traits in Rust by kalmar on Monday May 11, 2015 @11:29PM (#9529437)
What is the representation for a type like Box<Reader+Writer>? Is there an extra indirection to get each of the vtables? Is there synthesized combined trait type and just one vtable pointer?
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Re:Abstraction without overhead: traits in Rust by Jweb_Guru on Tuesday May 12, 2015 @01:23AM (#9529734)
I am pretty sure you can't actually construct such a type (at least not at the moment) so Rust sort of sidesteps the question.
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Re:Abstraction without overhead: traits in Rust by Manishearth on Tuesday May 12, 2015 @06:03AM (#9530570)
IIRC you can.
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Re:Abstraction without overhead: traits in Rust by Rusky on Tuesday May 12, 2015 @09:07AM (#9531409)
I get this when I try something like `as Box<Read+Write>`

    error: only the builtin traits can be used as closure or object bounds [E0225]
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Re:Abstraction without overhead: traits in Rust by Manishearth on Tuesday May 12, 2015 @09:32AM (#9531582)
TIL; thanks :)
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