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Nit: Change "Writer" to "Printer" in contravariance example #2145

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Aug 3, 2021
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Nit: Change "Writer" to "Printer" in contravariance example #2145

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2 changes: 1 addition & 1 deletion _tour/variances.md
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Expand Up @@ -54,7 +54,7 @@ printAnimalNames(dogs)

### Contravariance

A type parameter `A` of a generic class can be made contravariant by using the annotation `-A`. This creates a subtyping relationship between the class and its type parameter that is similar, but opposite to what we get with covariance. That is, for some `class Writer[-A]`, making `A` contravariant implies that for two types `A` and `B` where `A` is a subtype of `B`, `Writer[B]` is a subtype of `Writer[A]`.
A type parameter `A` of a generic class can be made contravariant by using the annotation `-A`. This creates a subtyping relationship between the class and its type parameter that is similar, but opposite to what we get with covariance. That is, for some `class Printer[-A]`, making `A` contravariant implies that for two types `A` and `B` where `A` is a subtype of `B`, `Printer[B]` is a subtype of `Printer[A]`.

Consider the `Cat`, `Dog`, and `Animal` classes defined above for the following example:

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