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Oct 5, 2021
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FAQ: small improvement in 'this type' answer #2195

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FAQ: small improvement in 'this type' answer
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7 changes: 6 additions & 1 deletion _overviews/FAQ/index.md
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Expand Up @@ -229,7 +229,12 @@ For an in-depth treatment of types vs. classes, see the blog post

### How can a method in a superclass return a value of the “current” type?

Possible solutions include F-bounded polymorphism
First, note that using `this.type` won't work. People often try that,
but `this.type` means "the singleton type of this instance", a
different and too-specific meaning. Only `this` itself has the
type `this.type`; other instances do not.

What does work? Possible solutions include F-bounded polymorphism
_(familiar to Java programmers)_, type members,
and the [typeclass pattern](http://tpolecat.github.io/2013/10/12/typeclass.html).

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