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supertrait

A trait that must already be implemented before another one can be.

trait B: A makes A a supertrait of B: every type implementing B must also implement A, and B's code may use A's methods. It is a requirement, not inheritance.

Examples

  • With trait Loggable: fmt::Display, impl Loggable for Order {} fails with E0277 until Order also implements Display.

See also

trait bound default method blanket implementation
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