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Programming Kotlin: should "variance" be "invariance"? (page 94)

vlastimir

vlastimir

Programming Kotlin: should "variance" be "invariance"? (page 94)

Title: Programming Kotlin: (page 94)
There is sentence:
In this section we’ll first review type variance, which is available in Java.
Should not it be:
In this section we’ll first review type invariance, which is available in Java.
Please tell me, if I am wrong I have deep misunderstanding of Java generics. Thank you.

1 comment
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First Post!

venkats

venkats

Author of Programming Kotlin, Rediscovering JavaScript (and 6 other titles)

Thank you for the question, Vlastimir.

Languages offer different variance for type in different situations, invariance, covariance, or contravariance. In the section we are going to review the type variance options.

Hope that helps.

Regards,

Venkat

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