Remove note about maybe scrapping contravariance

pull/68/head
Ryan Scheel 7 years ago committed by GitHub
parent 748a5e6742
commit 103b41c422
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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
refer to as "just" variance is in fact *covariance*. Rust has *contravariance*
for functions. The future of contravariance is uncertain and it may be
scrapped. For now, `fn(T)` is contravariant in `T`, which is used in matching
for functions. `fn(T)` is contravariant in `T`, which is used in matching
methods in trait implementations to the trait definition. Traits don't have
inferred variance, so `Fn(T)` is invariant in `T`).

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