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Oct 19, 2024
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FAQ: minor improvements to functions vs methods #3068

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FAQ: minor improvements to functions vs methods
SethTisue Sep 6, 2024
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SethTisue Oct 19, 2024
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19 changes: 10 additions & 9 deletions _overviews/FAQ/index.md
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Expand Up @@ -244,18 +244,19 @@ differ from a function value such as:

val square: Int => Int = x => x * x

For Scala 2, there is a [complete answer on Stack Overflow](https://stackoverflow.com/a/2530007/4111404)
For **Scala 2**, there is a [complete answer on Stack Overflow](https://stackoverflow.com/a/2530007/4111404)
and a [summary with practical differences](https://tpolecat.github.io/2014/06/09/methods-functions.html).

Note that in **Scala 3** the differences are fewer;
for example, they will be able to
[accept implicit parameters]({{ site.scala3ref }}/contextual/context-functions.html)
as well as [type parameters]({{ site.scala3ref }}/new-types/polymorphic-function-types.html).
In **Scala 3**, the differences are fewer.
[Context functions]({{ site.scala3ref }}/contextual/context-functions.html)
accept given parameters and
[polymorphic functions]({{ site.scala3ref }}/new-types/polymorphic-function-types.html)
have type parameters.

Nevertheless, it is still recommended to use methods most of the time,
unless you absolutely need a function. And, thanks to
[eta-expansion](https://stackoverflow.com/questions/39445018/what-is-the-eta-expansion-in-scala)
you rarely would need to define a function rather than a method.
Most code uses methods most of the time,
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IMHO we should not only note that most code uses methods but also encourage them as the default, given the syntax, performance, etc.

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Hmm. I see what you mean, but my intent was actually to make the wording stronger, not to weaken it. I think the word "recommend" is sort of weak. Whereas I really want to say quite forcefully, methods are definitely the norm in this language.

Maybe I can find a different wording.

unless a function value is actually needed. With
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In retrospect, we should have added an example, something like:

e.g. you will compose it with other functions using andThen.

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@SethTisue SethTisue Sep 6, 2024 •
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yes, good point, I can try to add something like that

[eta-expansion](https://stackoverflow.com/questions/39445018/what-is-the-eta-expansion-in-scala),
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I'm not sure if "With" is the best connector to use.
But, I am not known for my good level of written English 😅 it just feels off to me but that may as well be because I am not a native speaker.

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@SethTisue SethTisue Sep 6, 2024 •
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I actually hesitated over that; you're right to call it out.

Thanks for the feedback; I'll ponder some further edits.

a method can be converted as a function when needed.

### What's the difference between types and classes?

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