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Remove note about maybe scrapping contravariance

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Ryan Scheel 7 years ago committed by GitHub
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src/subtyping.md
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@ -46,8 +46,7 @@ subtyping of its outputs. There are two kinds of variance in Rust:
(For those of you who are familiar with variance from other languages, what we (For those of you who are familiar with variance from other languages, what we
refer to as "just" variance is in fact *covariance*. Rust has *contravariance* refer to as "just" variance is in fact *covariance*. Rust has *contravariance*
for functions. The future of contravariance is uncertain and it may be for functions. `fn(T)` is contravariant in `T`, which is used in matching
scrapped. For now, `fn(T)` is contravariant in `T`, which is used in matching
methods in trait implementations to the trait definition. Traits don't have methods in trait implementations to the trait definition. Traits don't have
inferred variance, so `Fn(T)` is invariant in `T`). inferred variance, so `Fn(T)` is invariant in `T`).

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